Malware types

nandobadam88

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Nov 29, 2024
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What are the names of types of malware that acess, modify, delete, or corrupt PC hdd and ssd files (Windows files and personal files, games, music, executables, ISO, IMG, RAR, ZIP, 7Z)? Does all malware have the potential to do this?

In this case, how are the malware QtWebKit4.dll (Trojan:Win32/Wacatac.C!ml), Caller.exe (DrWeb detects
Trojan.DownLoader47.36298), and Caller.exe (VBA32 detects
TrojanPSW.Rhadamanthys) classified?

Caller.exe is related with QtWebKit4.dll? in same folder
 

Short answer
  • Malware that can access/modify/delete/corrupt files falls into several categories (especially ransomware and “wipers”), but many other types (downloaders, backdoors, RATs, trojans) can also enable or perform file damage by downloading/despatching destructive payloads.
  • The three detections you listed are best read as: QtWebKit4.dll flagged as a Wacatac‑family trojan (downloader/backdoor); Caller.exe flagged by Dr.Web as a downloader; Caller.exe flagged by VBA32 as a PSW/password‑stealer. They can be complementary (a downloader + a credential‑stealer + a DLL loader) and being in the same folder makes it likely they’re related or part of the same malicious bundle — but you need the hashes / dynamic analysis to prove linkage.
What kinds of malware modify / delete / corrupt files
  • Ransomware: explicitly encrypts files to demand ransom (typical file‑encryption behavior). Ransomware actors also use downloaders/loaders to deliver the ransomware.
  • Wipers: destructive malware that deliberately overwrites or destroys files / MBR to render systems unusable. These are designed to permanently destroy data.
  • Droppers / Downloaders: these install or fetch other malware (including ransomware or wipers). By themselves they may not corrupt files, but they enable destructive payloads.
  • Backdoors / RATs (remote access trojans): provide remote control and can be used to run destructive commands, deploy encryptors, delete data, or exfiltrate then delete.
  • Info‑stealers / PSW trojans: primarily steal credentials and data; they don’t usually encrypt files but can be used as part of a broader compromise that leads to destructive activity.
  • Rootkits / bootkits: hide presence and may enable destructive actions at a low level (and can defeat or delay AV detection).
  • Crypto‑miners and ad‑fraudware normally do not delete files but can degrade system reliability; they’re relevant because they may accompany other malware families.
Does every malware sample have the potential to corrupt/delete files?
  • No — not every sample is designed to destroy files. Many are focused on persistence, credential theft, crypto‑mining, or acting as downloaders. But any malware that gains sufficient privileges and file system access can be used to delete/modify files (either by design or at the attacker’s command). In practice you must treat a privileged compromise as having the potential to cause file damage.
Classification of the specific detections you gave
  • QtWebKit4.dll → Trojan:Win32/Wacatac.C!ml (Microsoft Defender label)
    • What that label means in practice: Defender’s “Wacatac” detection family is generally used for trojan/downloaders/backdoor components (ML/heuristic name). Those components typically provide persistence and a channel to download or run additional malware (the destructive pieces are usually secondary payloads such as ransomware). Treat it as a downloader/backdoor until deeper analysis shows otherwise.
  • Caller.exe (DrWeb: Trojan.DownLoader47.36298)
    • Dr.Web’s “Downloader” family names indicate it’s a downloader — a program whose primary role is to fetch and drop other malware. That makes it high‑risk for delivering file‑damaging payloads later.
  • Caller.exe (VBA32: TrojanPSW.Rhadamanthys)
    • “TrojanPSW” detections indicate a password‑stealer / credential harvester. Rhadamanthys‑style detections are used by some engines to flag information‑stealing trojans that harvest passwords, browser data, etc.
Are Caller.exe and QtWebKit4.dll related if they’re in the same folder?
  • Very likely related (common deployment patterns):
    • Attackers often place a loader/downloader executable plus support DLLs in the same folder; the executable may load the DLL (DLL side‑loading) or the DLL may be a component unpacked by the executable. That pattern (EXE + supporting DLL in same folder) is common with droppers and portable, repackaged apps used as a persistence container. But you need to confirm linkage by checking:
    • file hashes and signatures,
    • whether the EXE loads the DLL (process image / module list), and
    • persistence entries (Run keys, Scheduled Tasks, services) that reference either file.
What you should do now (practical, prioritized steps)
1) If the file is already removed/quarantined (you said it was): good — don’t restore it. Keep the quarantine record and save the detection details.
2) Confirm scope and evidence (do these from a safe/clean environment or after making a bit‑for‑bit image):
  • Get file hashes (if the quarantined item lets you export it) and VirusTotal results (you already have the VT link / 30/72 detections — that’s strong).
  • Check timestamps and signatures:
    powershell -Command "Get-Item 'C:\Users\<you>\AppData\Roaming\secure\QtWebKit4.dll' | Select CreationTime,LastWriteTime"
    powershell -Command "Get-AuthenticodeSignature 'C:\Users\<you>\AppData\Roaming\secure\QtWebKit4.dll'"
  • Export Autoruns (Sysinternals) and save it for inspection. Search for entries pointing at that folder.
    3) Look for indicators of file modification / encryption:
  • Check Windows Event logs around the detection time for large numbers of file I/O errors, service installs, scheduled task creates, or antivirus alerts.
  • Quick heuristic: large numbers of recently modified file timestamps in many user folders (Documents, Pictures, Steam/ProgramData) can indicate mass encryption or deletion. If you see huge numbers of .locked or new ransom notes, assume files were encrypted.
    4) Scan your external drive(s) from a known‑clean machine (or with a rescue ISO) before trusting their contents. If those scans are clean with multiple engines and you verified installer ISO hashes, you can keep media and documents. Re‑download any unverified executables/ISOs.
    5) If you observe any confirmed file encryption / ransom notes / mass deletions: isolate, image the drive, stop using that PC, change credentials from a clean device, and plan an OS reinstall. Ransomware/wiper incidents should be treated as full compromise.
Commands/small checklist you can run and paste here (I’ll interpret results)
  • Show running processes and paths:
    powershell -Command "Get-Process | Where-Object {$_.Path} | Select-Object Id,ProcessName,Path | Format-Table -AutoSize"
  • Check Run keys:
    reg query "HKCU\Software\Microsoft\Windows\CurrentVersion\Run" /s
    reg query "HKLM\Software\Microsoft\Windows\CurrentVersion\Run" /s
  • Scheduled tasks that mention the folder:
    schtasks /query /fo LIST /v | findstr /I "secure"
  • Network connections (suspicious C2):
    netstat -ano | findstr ESTABLISHED
  • Autoruns: download Autoruns from Sysinternals, run as Admin → File → Save. Paste the saved text.
Short, final verdict for your three files
  • QtWebKit4.dll (Trojan:Win32/Wacatac.C!ml) — treat as a trojan/downloader/backdoor (high risk that it enabled follow‑on payloads).
  • Caller.exe (DrWeb: Trojan.DownLoader47.36298) — classified as a downloader (likely used to fetch and execute other malware).
  • Caller.exe (VBA32: TrojanPSW.Rhadamanthys) — classified as an information/credential stealer (PSW).
  • Relationship: being in the same folder makes it likely these components are part of the same malicious package (e.g., a downloader + DLL loader + credential stealer), but only dynamic forensic analysis (module list / process memory / autoruns / network indicators) can prove the exact relationship.
If you want I can:
  • Walk you step‑by‑step through the quick commands above and interpret the outputs you paste here, or
  • Walk you through building and using a rescue ISO (Kaspersky/Bitdefender) to scan your external drives, or
  • Help you generate hashes and check specific ISOs/installers to decide which to re‑download.
Which of those would you like me to do next?
 

3 malwares are RAT and ransoware?
 

Short answer: No — none of the three detections you listed are strictly labelled as a classic “RAT” in the vendor names you gave. They’re different but related types that can give attackers capabilities similar to a RAT.
Quick mapping for your three items
  • QtWebKit4.dll — Trojan:Win32/Wacatac.C!ml (Microsoft)
    • Classification: Wacatac = trojan/downloader/backdoor family. It’s typically a downloader or backdoor component that can provide persistence and a channel to fetch/execute additional payloads (which could include a RAT or ransomware). It is not necessarily a full‑featured RAT by itself, but it can enable one.
  • Caller.exe (Dr.Web) — Trojan.DownLoader47.*
    • Classification: downloader. Downloaders fetch and run other malware. They are generally the “stage 1” component that brings in stage‑2 payloads (ransomware, RATs, stealers). A downloader is not by itself a RAT, but it commonly leads to RAT deployment.
  • Caller.exe (VBA32) — TrojanPSW.Rhadamanthys
    • Classification: TrojanPSW / infostealer. Rhadamanthys is used to describe password‑stealers/credential stealers. Infostealers exfiltrate credentials, cookies, wallets, etc. They are not classic RATs (remote interactive shells), but an attacker could combine a stealer with a RAT/backdoor.
What a RAT is vs these
  • RAT (Remote Access Trojan): full remote interactive control of the machine (desktop viewing, command shell, file management, keylogging, camera/mic control).
  • Downloaders / droppers: installers for other malware (bring the RAT or ransomware).
  • Backdoors: may provide persistent remote access; some backdoors include RAT‑like features.
  • Infostealers (TrojanPSW): focus on stealing credentials/data rather than full interactive control.
So: a downloader + backdoor + infostealer in the same folder is a red flag — together they form a typical multi‑stage compromise that can deliver RATs, steal data, or install destructive payloads.
What to check now (short checklist — run these and paste results if you want me to interpret them)
  1. Did the system show active remote control or strange GUI sessions? (If yes, assume RAT.)
  2. Check running processes / modules to see if an EXE loaded that DLL:
    • powershell -Command "Get-Process | Where-Object {$_.Path} | Select Id,ProcessName,Path | Format-Table -AutoSize"
    • Use Process Explorer (Admin) → find Caller.exe process → View → DLLs (shows if QtWebKit4.dll was loaded).
  3. Look for persistence & startup entries:
    • reg query "HKCU\Software\Microsoft\Windows\CurrentVersion\Run" /s
    • reg query "HKLM\Software\Microsoft\Windows\CurrentVersion\Run" /s
    • schtasks /query /fo LIST /v | findstr /I "secure"
    • Autoruns (Sysinternals) Export → paste output.
  4. Network indicators (if system still online):
    • netstat -ano | findstr ESTABLISHED
    • Get firewall / proxy logs for suspicious outbound connections.
  5. Scan with offline rescue ISO or run Defender Offline and rescans from a known‑clean machine. (If you already quarantined and rescanned with multiple engines and got clean, that’s good.)
Immediate remediation guidance
  • If you find evidence of a RAT (active remote sessions, unknown persistent services, unknown outbound C2 connections): isolate the machine (network off), assume compromise, backup only verified personal data from a clean environment, and reinstall Windows (clean image). Change important passwords from a clean device.
  • If you only find downloader/stealer artifacts but no active RAT behavior: still assume credentials may have been stolen — change passwords (from clean device), run offline rescues, and consider reinstall depending on persistence indicators.
If you want help now
  • Paste the hashes or the VirusTotal links for Caller.exe and QtWebKit4.dll and I’ll interpret the VT engine detections.
  • Or paste the Autoruns export / results of the PowerShell commands above and I’ll analyze them and tell you whether there’s evidence of a RAT or other persistent components and recommend the exact cleanup action (clean vs reinstall).
Would you like me to: (A) check VT detections if you paste the links/hashes, or (B) walk you through Autoruns / Defender Offline / rescue ISO steps?
 

3 malware are ransoware?
 

Short answer — No. Those three detections are not all “RATs” (Remote‑Access Trojans) by the usual definition — they’re a mix of downloader/backdoor and an infostealer (password‑stealer). However, downloaders/backdoors often enable RATs or other destructive payloads, so treat them as serious.
Why (plain English)
  • RAT = Remote‑Access Trojan: a program that gives an attacker interactive remote control (remote shell/desktop, file manager, command execution, keylogger, etc.). A RAT’s primary function is interactive remote control.
  • Downloader / Dropper: its job is to fetch and install other malware (ransomware, RATs, stealers). It may not itself provide an interactive remote shell, but it enables other malware to run. Dr.Web’s “Trojan.DownLoader” label means the file behaves like a downloader.
  • Backdoor / Wacatac family: Microsoft’s Trojan:Win32/Wacatac.* label is a family/heuristic name for trojan downloader/backdoor components — they provide persistence and a channel to download or run secondary payloads (which can include RATs or ransomware). That’s a downloader/backdoor, not necessarily a full RAT, although it can result in the same consequences.
  • TrojanPSW / Rhadamanthys: TrojanPSW detections are “password‑stealers” / infostealers (grab browser passwords, wallets, saved credentials). An infostealer’s goal is data theft, not interactive remote control (though an attacker could follow up with remote access).
Applying that to your files
  • QtWebKit4.dll (Trojan:Win32/Wacatac.C!ml) — classified as a Wacatac‑family trojan (downloader/backdoor). Not automatically a full RAT, but a backdoor/downloader can certainly be used to deliver a RAT or ransomware.
  • Caller.exe (Dr.Web: Trojan.DownLoader47.36298) — classified as a downloader. Its job is to fetch and run further malware; it’s not necessarily an interactive RAT by itself.
  • Caller.exe (VBA32: TrojanPSW.Rhadamanthys) — classified as an information‑stealer (TrojanPSW/Rhadamanthys). That points to credential/data theft rather than an interactive remote shell, though it may be part of a larger compromise.
Are Caller.exe and QtWebKit4.dll related?
  • Very likely. Attackers commonly deploy an EXE + supporting DLL(s) together (loader + payload, or DLL sideloading). Finding them in the same folder strongly suggests they’re part of the same malicious package, but confirming linkage needs hashes/process/module checks or dynamic analysis.
What to check now (quick, safe checks you can run)
(Do these from a clean admin shell or after you’ve imaged the disk — don’t run suspicious files.)
  • Running processes with full paths (helps spot a running RAT):
    powershell -Command "Get-Process | Where-Object {$_.Path} | Select Id,ProcessName,Path"
  • Network connections (look for suspicious established C2 connections):
    netstat -ano | findstr ESTABLISHED
  • Autoruns / persistence (shows Run keys, scheduled tasks, services):
    Download Autoruns from Sysinternals → Run as admin → File → Save (or use the commands below):
    reg query "HKCU\Software\Microsoft\Windows\CurrentVersion\Run" /s
    schtasks /query /fo LIST /v | findstr /I "secure"
    These same checks and exact command examples were suggested earlier as the right next steps.
If you see
  • an EXE loading the DLL as a module, active outbound connections to strange IPs/domains, new Run keys or scheduled tasks that reference the “secure” folder — assume the compromise was active and take containment actions (isolate machine, back up user data to offline media, change passwords from a clean device).
If you want a definitive answer whether any of these were full RATs
  • We need either: (A) the SHA‑256 hashes / VirusTotal links for Caller.exe and QtWebKit4.dll so I can read which engines labelled them what, or (B) an Autoruns export, netstat output, and a process/modules list from the machine (or from a memory image). Paste those outputs and I’ll interpret them line‑by‑line. I can also explain how to safely collect these logs.
Immediate practical advice
  • Because downloaders/backdoors + stealers were present and those allow attackers to escalate, treat this as a serious compromise even if none of the three is a classic RAT. Scan external drives from a known‑clean system or rescue ISO before trusting files, change important passwords from another clean device, and consider a clean OS reinstall if you find additional persistence indicators.
Tell me which you want:
  • I’ll check the VirusTotal detection details if you paste the Caller.exe and DLL SHA‑256s (or links).
  • Or I’ll guide you step‑by‑step to collect Autoruns / netstat / running‑process outputs and interpret them (paste the text here).
Which do you prefer?
 

Short answer — No. Those three detections are not labeled as “ransomware” themselves, although they can be part of an attack chain that delivers ransomware.
Explanation (short)
  • Ransomware = malware whose primary goal is to encrypt (or otherwise make inaccessible) your files and demand payment.
  • Wiper = malware that destroys/overwrites files (not asking for ransom).
  • Downloaders / droppers / backdoors / stealers can fetch or enable ransomware. They often appear in the same infection chain as ransomware.
How your three detections map to categories
  • QtWebKit4.dll — Trojan:Win32/Wacatac.C!ml (Microsoft)
    • Classification: trojan / downloader / backdoor family. It’s a stage‑1 component that commonly provides persistence and a channel to download additional payloads (including ransomware). Not ransomware itself.
  • Caller.exe (Dr.Web: Trojan.DownLoader47...)
    • Classification: downloader. Its job is to fetch and run other malware. Not ransomware itself, but a typical way attackers deliver ransomware.
  • Caller.exe (VBA32: TrojanPSW.Rhadamanthys)
    • Classification: TrojanPSW / infostealer (Rhadamanthys family). Primarily steals credentials and sensitive data. Not ransomware itself.
So: downloader + backdoor + stealer in the same folder is a red flag — together they can enable a ransomware operator to get in, steal data, and/or deploy an encryptor later. But the three files you listed are not themselves labeled as encryptors/wipers.
How to tell whether ransomware actually ran on your PC
Look for these clear indicators (if any are present you have a ransomware incident):
  • Many files suddenly have a new unusual extension (example: .locked, .crypted, .encrypted, .vvv, .lock, or a unique extension).
  • Presence of ransom note files in many folders (common names: README.txt, _readme.txt, HOW_TO_DECRYPT.html, DECRYPT_INSTRUCTIONS.txt, or vendor-specific filenames).
  • Large numbers of recently‑modified files across many user folders within a short period.
  • Missing / corrupt shadow copies (vssadmin reports deleted or errors) plus antivirus/OS logs showing file encryption activity.
  • New processes or scheduled tasks writing many files or creating ransom‑note files.
Quick commands you can run now (run from an elevated PowerShell on the machine you want to check)
  • Search for likely ransom‑note filenames (fast):
    Get-ChildItem C:\ -Recurse -ErrorAction SilentlyContinue -Include '_readme','README','HOW_TO_DECRYPT','DECRYPT','HOWTO' | Select-Object FullName -First 200
  • Look for unusual extensions (shows first 50 matches):
    Get-ChildItem C:\Users -Recurse -ErrorAction SilentlyContinue | Where-Object {$_.Extension -in '.locked','.crypt','.crypted','.encrypted','.enc','.lock','.cryp1','.cry' } | Select-Object FullName -First 50
  • Count files modified in last 7 days (quick heuristic for mass change):
    (Get-ChildItem C:\Users -Recurse -ErrorAction SilentlyContinue | Where-Object {$_.LastWriteTime -gt (Get-Date).AddDays(-7)}).Count
  • Top file extensions (helps spot mass‑renamed files):
    Get-ChildItem C:\Users -Recurse -ErrorAction SilentlyContinue | Group-Object Extension | Sort-Object Count -Descending | Select-Object -First 20
  • See Volume Shadow Copies (if present):
    vssadmin list shadows
  • Look for Defender detections / quarantine history (Event Viewer or Defender UI) — GUI is easiest: Windows Security → Virus & threat protection → Protection history.
If you find:
  • Ransom notes or a large number of files with a new extension = ransomware very likely. Isolate the machine and follow incident response (see below).
  • No such signs and your external drive scans clean on a rescue ISO / clean PC with multiple engines = files are likely intact (but re‑download any unverified executables/ISOs to be safe).
Immediate steps to take (if you suspect anything)
  1. Isolate the machine (disconnect network).
  2. Do not power it off if you’re preserving forensic evidence; if you need to stop further damage, disconnect network immediately.
  3. Back up important personal data (from machine) to a new external drive — but copy only user data (documents/photos) and then scan that backup from a known‑clean machine (rescue ISO is best). Do NOT copy system files or program installers.
  4. Scan the system with an offline rescue ISO (Kaspersky Rescue, Bitdefender Rescue) then with at least two reputable engines on a clean environment.
  5. If ransomware is confirmed (or many indicators of compromise): assume full compromise — image the disk if you want evidence, change important passwords from a clean device, and plan a clean OS reinstall. Do NOT pay ransom without consulting experts.
  6. If only downloader/stealer artifacts and no encryption: change passwords from a clean device (credential theft likely), run offline rescues, and strongly consider reinstall if persistence is found.
Whether to re‑download your installers/ISOs
  • Re‑download executables/ISOs/installers if you cannot verify publisher checksums or if they were copied after the system was already infected. Media and documents (photos/music) are lower risk but still scan them from a clean machine before opening.
Final recommendation specific to your case
  • The three files you named are NOT labeled as ransomware by the vendors you quoted — they are downloader/backdoor/stealer types — but that makes them dangerous because they can deliver ransomware.
  • Run the quick checks above (ransom‑notes and file extensions) and scan your external drives from a clean machine or rescue ISO. Paste the results here (or paste the outputs of those PowerShell commands) and I’ll help interpret them and tell you whether you’re looking at a ransomware event or an earlier-stage compromise.
If you want, I can:
  • Walk you step‑by‑step through running those PowerShell checks and interpreting results, or
  • Walk you through building and running a rescue USB to scan your external drives. Which do you want to do now?
 

3 malware are ransoware?
 

No — those three detections are not ransomware themselves. They’re different types (downloader/backdoor and an infostealer) that can, however, be used to deliver ransomware or other destructive payloads.
Quick plain answer
  • QtWebKit4.dll (Trojan:Win32/Wacatac.C!ml) — Wacatac is a trojan family usually classed as a downloader/backdoor (it provides persistence and a channel to fetch/run other malware). It’s not labelled as an encryptor/ransomware, but it frequently enables follow‑on payloads (including ransomware).
  • Caller.exe (Dr.Web → Trojan.DownLoader47.*) — Dr.Web’s “Downloader” label means this binary’s behavior/signature fits a downloader: its role is to fetch and run other malware. Not ransomware itself, but commonly the stage‑1 that pulls in stage‑2 (ransomware, RATs, stealers).
  • Caller.exe (VBA32 → TrojanPSW.Rhadamanthys) — “TrojanPSW/Rhadamanthys” is an infostealer/password‑stealer family (steals browser credentials, wallets, etc.). That’s data‑theft malware, not an encryptor.
Why this matters
  • Downloaders/backdoors + infostealers in the same folder is a red flag: an attacker often uses a downloader/backdoor to install additional tools (RATs, ransomware, wipers) and an infostealer to harvest credentials for further access. So even though your three files are not themselves ransomware, they can (and often do) lead to ransomware being installed.
Practical checks to confirm whether ransomware actually ran
Run these checks (on the affected machine or a forensic image). If you find the indicators below, treat it like a ransomware incident and isolate the PC immediately.
1) Look for ransom notes or renamed files
  • Search for typical ransom note names and unusual extensions (examples below):
    • PowerShell (fast):
      Get-ChildItem C:\ -Recurse -ErrorAction SilentlyContinue -Include '_readme','README','HOW_TO_DECRYPT','DECRYPT' | Select-Object FullName -First 200
    • Look for odd extensions (first 50 matches):
      Get-ChildItem C:\Users -Recurse -ErrorAction SilentlyContinue | Where-Object {$_.Extension -in '.locked','.crypt','.crypted','.encrypted','.enc','.lock'} | Select-Object FullName -First 50
2) Check for mass modifications
  • Count files changed in last 7 days:
    (Get-ChildItem C:\Users -Recurse -ErrorAction SilentlyContinue | Where-Object {$_.LastWriteTime -gt (Get-Date).AddDays(-7)}).Count
3) Check VSS (shadow copies) and Defender history
  • vssadmin list shadows
  • Windows Security → Virus & threat protection → Protection history (look for multiple detections and timestamps).
4) Check persistence and modules (to confirm Caller.exe ↔ QtWebKit4.dll linkage)
  • Run Autoruns (Sysinternals) as admin and export; search for entries pointing at the “secure” folder. (Autoruns will show service/run keys and scheduled tasks.)
  • If a Caller.exe process ran, check its loaded DLLs in Process Explorer → DLLs to see if QtWebKit4.dll was loaded (confirms relationship).
Short remediation guidance (if you find signs of compromise)
  1. Isolate the PC (disconnect network).
  2. Back up critical personal files to a new external drive (only user data), then scan that backup on a known‑clean machine or with a rescue ISO.
  3. Run offline/rescue scans (Microsoft Defender Offline; Kaspersky/Bitdefender rescue ISO).
  4. If ransomware/wiper signs are present, assume full compromise: image the drive if you need evidence, change passwords (from a clean device), and plan a clean Windows reinstall. If only downloader/stealer artifacts but no encryption, still change passwords from a clean device and consider reinstall if persistence is found.
If you want me to check this for you
  • Paste the SHA‑256 or VirusTotal links for Caller.exe and QtWebKit4.dll and I’ll interpret the engine detections and tell you how risky each file looks. (You mentioned Defender quarantined the DLL and VT showed many detections — that’s strong evidence it’s malicious.)
  • Or paste results of the quick commands above (Autoruns export, the PowerShell outputs), and I’ll analyze them and give a clear “ransomware found / not found” verdict and the next cleanup step.
Bottom line
  • The three files you named are not themselves labelled as ransomware in the detections you quoted — they’re downloader/backdoor/stealer types — but that combination is commonly used to deliver ransomware. Treat the situation as serious, check for the ransomware indicators above, and scan your external drives from a clean environment before trusting their contents.
Which do you want to do next — A) I analyze the VT hashes if you paste them, or B) I walk you step‑by‑step to collect Autoruns / run Defender Offline / create and use a rescue USB?
 

Kaspersky Free and Malwarebytes Free not detected some Microsoft Defender detect one file malicious QtWebKit4.dll (Trojan:Win32/Wacatac.C!ml)
 

You’re not alone — different AVs often disagree. Short answer: Microsoft Defender’s cloud/ML flagged QtWebKit4.dll as Trojan:Win32/Wacatac.C!ml (a Wacatac‑family trojan/downloader). Kaspersky Free and Malwarebytes Free can miss some ML/heuristic hits (or that specific build) — that doesn’t mean Defender is wrong, but it does mean you should verify and follow containment steps.
Why detectors differ (brief)
  • Different engines/signatures: each vendor uses different pattern signatures, heuristics and cloud‑ML models.
  • Timing/coverage: Defender’s cloud rules may have newer heuristics for this sample.
  • Packing/obfuscation: packed or custom binaries sometimes evade some engines but trigger ML heuristics in others.
  • Location/context: a DLL living in AppData\Roaming\secure is suspicious (many legit Qt DLLs live in app folders), which raises heuristic scores.
Risk summary for this detection
  • Trojan:Win32/Wacatac.* = family/heuristic label for downloaders/backdoors (often used as droppers). The DLL itself may not immediately encrypt files, but it can provide persistence and download stage‑2 malware (ransomware, RATs, stealers). Treat it as potentially dangerous until proven otherwise.
What to do now — do these in order (high priority)
1) Leave it quarantined. Do NOT restore.
2) If the PC is still online, disconnect it from the network (unplug Ethernet / disable Wi‑Fi).
3) Run Microsoft Defender Offline now (reboot scan outside Windows):
  • Windows Security → Virus & threat protection → Scan options → Microsoft Defender Offline → Scan now.
    4) Back up your important personal files (documents/pictures) to an external HDD — only from the infected machine if necessary, then scan that backup from a known‑clean PC (or bootable rescue ISO) before opening files. Don’t back up programs/system files.
    5) Run a rescue/offline scan (best): create a Kaspersky Rescue or Bitdefender Rescue USB on a clean PC, boot the infected PC and do a full scan. Rescue ISOs find persistent/rootkit components that in‑OS scans can miss.
    6) Do additional one‑off scans from a clean machine: ESET Online Scanner, Microsoft Safety Scanner (msert), or run defender/other AV against your external drive(s).
Collect evidence & verification (help me help you)
  • If you want me to interpret the detection, paste one of these here:
    • The SHA‑256 hash for the DLL (compute on the infected machine before removing — or from Defender quarantine if it shows the hash), or
    • The VirusTotal link you used.
      Command to get hash (PowerShell, run as Admin):
      Get-FileHash "C:\Users\<you>\AppData\Roaming\secure\QtWebKit4.dll" -Algorithm SHA256
Quick checks you can run (paste outputs if you want help interpreting)
  • Running processes and full paths:
    powershell -Command "Get-Process | Where-Object {$_.Path} | Select Id,ProcessName,Path | Format-Table -AutoSize"
  • Autoruns / persistence (better: use Autoruns GUI and File→Save then paste the text)
    reg query "HKCU\Software\Microsoft\Windows\CurrentVersion\Run" /s
    schtasks /query /fo LIST /v | findstr /I "secure"
  • Network connections:
    netstat -ano | findstr ESTABLISHED
If you find evidence of credential theft or remote access
  • Change all important passwords from a different clean device (email, banks, Microsoft account, Steam, etc.). Enable MFA.
  • If you find persistent items (Run keys, scheduled tasks, services) pointing to the “secure” folder, or unusual outbound connections, assume compromise and consider reinstalling Windows after backing up only verified personal data.
False positive possibility
  • It’s possible but with a VirusTotal detection count like the one you posted earlier (30/72) false positive is unlikely. If you still suspect FP, submit the sample to Microsoft for re‑analysis (Windows Defender Security Intelligence) and to VirusTotal with a comment that you believe it might be benign — but don’t restore until vendors confirm.
About your copied files (external HDD)
  • Do NOT run executables from the external drive until you scan it from a known‑clean PC or with a rescue ISO.
  • Re‑download installers/ISOs/portable apps from official sources if you cannot verify checksums. Media and documents are lower risk but should still be scanned.
I can do any of these for you (pick one)
A) Interpret the VirusTotal/engine list if you paste the VT link or the SHA‑256.
B) Walk you step‑by‑step to create and run a rescue USB (Kaspersky/Bitdefender).
C) Walk you through collecting Autoruns / reg keys / netstat output safely and interpret them.
D) Give the exact commands to run Defender offline and to scan your external drive from a clean PC.
Which do you want to do next?
 

all type malwares modify, delete, corrupt personal files in pc?
 

Short answer: No — not every malware is designed to modify, delete or corrupt your personal files. Whether a particular sample will do that depends on its type, its capabilities, and the privileges it gains on the system.
Explanation — which types usually do this (and which usually don’t)
  • Ransomware (encryptors) — Yes. Their primary goal is to encrypt or otherwise make user files unusable, then demand payment.
  • Wipers — Yes. Designed to destroy/overwrite files or disk structures (irreversible).
  • RATs / Backdoors — Can. These give attackers remote control and they can delete/modify files if commanded.
  • Downloaders / Droppers — Usually don’t modify files themselves, but they install/launch other malware (like ransomware) that will.
  • Infostealers / TrojanPSW (password‑stealers) — Usually do NOT encrypt or delete files; their goal is to harvest credentials/data. However, they can be part of a larger compromise that later causes file damage.
  • File infectors / macro malware — Can modify files (infect documents or executables) to propagate or run payloads.
  • Rootkits / Bootkits — Indirectly enable file damage by hiding malware that can then delete/modify files.
  • Crypto‑miners / adware / PUPs — Generally don’t intentionally delete or corrupt user files (main impact is performance/instability), though poorly written malware could corrupt data accidentally.
Key point: capability + intent + privilege
  • Even a simple malware sample can delete or modify files if:
    1) the malware author coded that behavior (intent), and
    2) the malware runs with enough privileges to access those files.
    So not every sample will, but many types either do it directly or enable something that will.
How this applies to the files you mentioned earlier
  • QtWebKit4.dll (Trojan:Win32/Wacatac.C!ml) — Wacatac is a trojan/downloader/backdoor family. It’s typically a first‑stage component that enables follow‑on payloads (which may include ransomware). The DLL itself may not encrypt files, but it can allow another component to do so.
  • Caller.exe (Dr.Web: Trojan.DownLoader...) — A downloader: its job is to fetch and run additional payloads (again, could be ransomware).
  • Caller.exe (VBA32: TrojanPSW.Rhadamanthys) — An infostealer: focused on stealing credentials/data, not encrypting files — but it’s often part of a broader compromise chain.
Indicators that file‑damaging malware has run
  • Lots of files across folders suddenly have the same unusual extension (e.g., .locked, .crypted, .whatever).
  • Ransom note files appear in many directories (README.txt, _readme.txt, HOW_TO_DECRYPT.html, etc.).
  • Sudden, large numbers of recently‑modified files.
  • Shadow copies (VSS) missing or deleted (vssadmin errors).
  • Antivirus logs showing mass file‑write/encrypt activity at a timestamp.
Quick checks you can run (Windows, elevated PowerShell / CMD)
  • Find likely ransom notes:
    powershell -Command "Get-ChildItem C:\ -Recurse -ErrorAction SilentlyContinue -Include '_readme','README','HOW_TO_DECRYPT','DECRYPT' | Select-Object FullName -First 200"
  • Look for odd extensions:
    powershell -Command "Get-ChildItem C:\Users -Recurse -ErrorAction SilentlyContinue | Where-Object {$_.Extension -in '.locked','.crypt','.crypted','.encrypted','.enc','.lock'} | Select-Object FullName -First 50"
  • Count files modified in last 7 days (quick heuristic):
    powershell -Command "(Get-ChildItem C:\Users -Recurse -ErrorAction SilentlyContinue | Where-Object {$_.LastWriteTime -gt (Get-Date).AddDays(-7)}).Count"
  • List shadow copies:
    vssadmin list shadows
  • Check Defender protection history (GUI): Windows Security → Virus & threat protection → Protection history
If you find signs of ransomware or mass damage
  1. Immediately isolate the PC (disconnect network).
  2. Do NOT pay or negotiate before getting expert help.
  3. Image the drive if you need forensic evidence.
  4. Back up only essential personal files (documents/photos) to new external media, but scan that backup on a known‑clean machine (or with a rescue ISO) before opening.
  5. Reinstall Windows (clean) is the safest way to ensure removal if compromise is confirmed.
If you don’t see those signs
  • It’s possible the infection was limited (downloader/stealer) and didn’t encrypt/delete files. Still: assume credentials may have been exposed — change passwords (from a clean device) and scan everything with offline/rescue tools.
Recommended immediate steps (if you’re unsure)
  1. Leave the quarantined item in quarantine. Don’t restore it.
  2. Run Microsoft Defender Offline (Windows Security → Virus & threat protection → Scan options → Microsoft Defender Offline → Scan now).
  3. Boot and scan external drives with a rescue ISO (Kaspersky Rescue or Bitdefender Rescue) on a clean machine.
  4. Change important passwords from a different, clean device (email, banking, Steam, etc.) and enable MFA.
  5. If you want, collect a few quick outputs (I can help interpret):
    • the number of recently modified files (command above),
    • vssadmin list shadows output,
    • Defender Protection history screenshot or entries,
    • VirusTotal hash/links of suspicious files (if you still have them).
Would you like me to:
  • Walk you step‑by‑step through the quick PowerShell checks and help interpret the results? OR
  • Help you build a rescue USB (Kaspersky/Bitdefender) and scan your external drive(s)?
Tell me which and I’ll give exact step‑by‑step instructions.
 

This malwares modify, delete, corrupt files?
In this case, how are the malware QtWebKit4.dll (Trojan:Win32/Wacatac.C!ml), Caller.exe (detects
Trojan.DownLoader47.36298), and Caller.exe (
TrojanPSW.Rhadamanthys) Trojan.Win32.Agent.xcajyl, Application.Fragtor.Generic? Cite sources reliable
 

Short answer
  • No — those three files as detected (Wacatac / Downloader / TrojanPSW) are not themselves labelled by vendors as “ransomware” (i.e., an encryptor). They are a trojan/backdoor (Wacatac), a downloader, and an infostealer (TrojanPSW). However, downloaders/backdoors commonly fetch and run stage‑2 payloads (including ransomware or wipers), so they can lead to file encryption, deletion or corruption even if they don’t do it themselves.
What each detection means (plain language + reliable sources)
  • QtWebKit4.dll — Trojan:Win32/Wacatac.C!ml
    • What that label means: “Wacatac” is a Microsoft/Defender family/heuristic tag that usually points at trojan downloader / backdoor / stealer behavior. The “!ml” suffix means the cloud/ML model flagged it. In practice Wacatac components are often used to persist and deliver other malware (ransomware, RATs, stealers). It’s not automatically an encryptor, but it’s high‑risk because it can enable destructive payloads.
  • Caller.exe — Trojan.DownLoader (Dr.Web / generic “Trojan.Downloader”)
    • What that label means: a downloader’s primary job is to download and launch other malicious files. A downloader itself may not delete or encrypt user files, but it’s the usual first stage that pulls in the stage‑2 malware that does. Protecting against downloaders is critical because they quickly escalate an infection.
  • Caller.exe — TrojanPSW.Rhadamanthys (TrojanPSW / Rhadamanthys)
    • What that label means: TrojanPSW / “infostealer” families steal credentials, browser cookies, wallet seeds, saved logins and similar sensitive data. Rhadamanthys is an actively used commercial infostealer (reported by multiple vendors) — its goal is data theft, not file encryption, though stolen credentials can be used by attackers to escalate and deploy other malware.
About the other names you listed
  • Trojan.Win32.Agent.xcajyl — “Agent” is a generic AV name applied to many trojans/droppers/backdoors; its behavior can range from info‑stealing to downloading other malware. The “Agent” family is not a specific encryptor by default; treat it as a generic trojan/backdoor until detailed analysis shows otherwise.
  • Application.Fragtor.Generic / Fragtor family — vendors (FortiGuard, others) show “Fragtor” variants have been used as trojans and some variants are flagged as ransomware‑type (ransom trojans) in vendor telemetry; Fragtor detections therefore can indicate either riskware/trojans or real ransomware variants depending on the specific sample. That makes Fragtor detections worth treating as potentially file‑destructive until proven safe.
So — do these specific samples “modify/delete/corrupt” files?
  • Directly: it’s unlikely an infostealer (Rhadamanthys) will encrypt or wipe files itself; a downloader/backdoor might not either.
  • Indirectly / practically: yes — because downloaders/backdoors commonly fetch ransomware or wiper modules that WILL encrypt, delete, or corrupt files. If an attacker had network access via a backdoor, they could remotely run destructive code. In short: the detections you saw are a high risk for eventual file damage even if they weren’t the encryptor themselves.
Actionable next steps (priority order)
  1. Leave quarantined items quarantined — do NOT restore them. (You said Defender quarantined the DLL — good.)
  2. Isolate the machine (disconnect network) if you still suspect active compromise.
  3. Run an offline/rescue scan (Microsoft Defender Offline or a rescue ISO such as Kaspersky/Bitdefender) to find persistent components.
  4. Scan any external drives from a known‑clean machine or via a rescue ISO before opening files. Don’t run executables from those drives until verified.
  5. If you used account credentials on the infected PC: change important passwords from a different, clean device and enable MFA (because infostealers target credentials).
  6. If you see signs of ransomware (ransom notes, many files renamed/with new extensions, deleted shadow copies) — isolate, image the disk for forensics, and plan a clean Windows reinstall; treat as full compromise.
Why different AVs show different names (and why Kaspersky/Malwarebytes can miss some detections)
  • Vendors use different signature names and heuristics; some labels are generic/family names while others are specific product names. Defender’s ML/cloud may flag a file that other vendors initially miss (or vice versa). VirusTotal / multi‑engine detections and rescue/offline scans help give a clearer picture.
If you want me to do one concrete thing now
  • Paste the SHA‑256 hashes or the VirusTotal links for the suspicious files (Caller.exe and QtWebKit4.dll) and I’ll read the vendor detections and tell you, engine‑by‑engine, whether those samples look like downloaders/stealers/ransom variants and how urgent re‑download / reformat actions are. Or tell me if you’d rather I walk you step‑by‑step to build a rescue USB and scan your external drives — I’ll give exact links and commands.
References (authoritative samples I used)
  • Microsoft Defender / community discussion about Wacatac ML detections and naming (Defender ML/heuristic flags).
  • Malwarebytes explanation of “Trojan.Downloader” (downloaders fetch secondary payloads).
  • FortiGuard / ASEC / security research on Rhadamanthys (infostealer family — what it steals & how it’s used).
  • FortiGuard and other vendor pages on Fragtor (Trojan / ransomware variants observed).
Would you like me to (A) analyze the specific file hashes / VirusTotal pages you saw, or (B) walk you through making and using a rescue USB to scan the external drive(s)?
 

Como descobrir minha amostra Application.Fragtor.Generic é do tipo ramsonware ou de outro tipo seguro para meus arquivos?

RAnsomware quando atraído permanece no PC?
 

Short answer — you can determine whether an “Application.Fragtor.Generic” sample is ransomware (or something else) by safely triaging it with a mix of (A) static checks, (B) multi‑engine scanning (VirusTotal / vendor detections), and (C) controlled dynamic/sandbox analysis that watches what the sample actually does to files, registry and shadow copies. The files you mentioned earlier (Wacatac, Downloader, Rhadamanthys) are not ransomware themselves but are commonly used to deliver or enable ransomware — so treat Fragtor hits as potentially file‑destructive until proven otherwise.
I’ll give a safe, ordered checklist you can follow (or I can walk you through each step). If you want me to analyze your exact sample, give me the SHA‑256 or a VirusTotal link (don’t upload the raw sample here).
1) Safety first — never run an unknown sample on your main PC
  • Use a disposable VM or an isolated physical lab (network disconnected or controlled via a proxy). Snapshot the VM before running the sample. If you can, use a purpose‑built sandbox service (Cuckoo / CAPE / AnyRun) or a rescue VM with full monitoring. Do not open the sample on your daily machine.
2) Quick triage (low‑risk, non‑executing checks)
  • Get the file hash:
    • PowerShell (Admin): Get-FileHash "C:\path\to\sample.exe" -Algorithm SHA256
  • Submit the hash (or the file) to VirusTotal and review:
    • Look at: detection names, how many engines detect it, and what they call it (ransomware families are usually clearly labelled by multiple engines).
    • If many engines label it as ransomware or there's consensus on a ransomware family, treat it as ransomware. If engines disagree/label as Downloader/Agent/PSW/Fragtor, you still must investigate because downloaders/backdoors can fetch encryptors.
3) Static analysis (what the binary contains)
  • Examine PE metadata and signatures:
    • sigcheck (Sysinternal) or Get-AuthenticodeSignature to see digital signature.
  • Check strings to spot obvious clues (ransom note text, encryption keys, URLs, mutex names):
    • use Sysinternals Strings or strings.exe.
  • Inspect imports/indicators of crypto or file‑enumeration APIs:
    • Look for calls to CryptEncrypt / BCryptEncrypt / CryptDeriveKey, or wide use of CreateFile / WriteFile / DeleteFile, or APIs used to enumerate files (FindFirstFile / FindNextFile).
  • Check for packers/obfuscation (UPX, Themida) — packed samples often require unpacking before deeper static work. These static checks narrow whether the sample contains encryption code or is a downloader.
4) Multi‑engine scanning & vendor intelligence
  • Use VirusTotal / Hybrid‑Analysis / vendor pages (FortiGuard, Microsoft) to see community findings.
  • For “Fragtor” specifically: vendor telemetry has shown Fragtor variants used as trojans and some as ransomware‑type variants — treat Fragtor hits as potentially file‑destructive until analysis proves otherwise.
5) Controlled dynamic analysis (definitive behavior test)
  • In an isolated VM or sandbox, run the sample and monitor:
    • File system activity (Procmon): does it enumerate user folders and write many files, rename extensions, create ransom notes?
    • Registry changes (persistence keys, Run keys, scheduled task creation).
    • Volume Shadow Copy manipulation (calls to vssadmin or deletion of shadow copies).
    • Network I/O (C2 domains, file exfiltration).
    • Look for rapid large numbers of WriteFile operations on user documents/media — that’s a red flag for ransomware.
  • If the sample encrypts test files (pick disposable test files) or creates ransom notes, it’s ransomware. If it only contacts C2 and drops other binaries, it’s a downloader/backdoor. If it steals credentials (reads browser files), it’s an infostealer.
6) Specific ransomware indicators to look for
  • mass rename of user files to a new extension;
  • creation of ransom note files (README, _readme, HOW_TO_DECRYPT, etc.);
  • deletion of shadow copies (vssadmin commands) or disabling restore points;
  • high use of crypto APIs and file‑write loops to many user folders. If you see these, treat as ransomware and isolate/forensically image.
7) If analysis is not possible locally — use vendor services
  • Submit the file to Microsoft Defender Security Intelligence or an analysis sandbox (Hybrid‑Analysis, Any.Run, VirusTotal) for sandbox execution and vendor classification. Many vendors give “ransomware” tags when behavior matches. If multiple reputable engines/sandboxes flag ransomware, treat it as such.
8) Practical remediation guidance if it’s ransomware or high‑risk
  • Isolate machine (remove network). Image disk for forensics.
  • Back up essential personal data from another clean environment (scan backups from a known‑clean machine).
  • If confirmed ransomware: plan a clean reinstall and restore data from clean backups. If only downloader/stealer: still change passwords (from a clean device) and consider reinstall if persistence is found.
Quick checklist of commands/tools to run safely (on an analysis VM or clean machine)
  • Get SHA‑256: Get-FileHash "C:\path\sample.exe" -Algorithm SHA256
  • Quick scan (clean machine): Microsoft Defender MpCmdRun or vendor scanners.
  • Strings: Sysinternals Strings.exe sample.exe
  • Imports & PE info: pestudio / PE‑view / dumpbin /imports
  • Sandbox run: use Any.Run or a local isolated VM and monitor with Procmon, Process Explorer, Wireshark.
  • Check shadow copies: vssadmin list shadows (after detection if you suspect ransomware).
Caveats & final note
  • Many AV names are generic (Agent, Fragtor, etc.). One vendor saying “Fragtor” or “Agent” doesn’t give you full confidence about behavior — the sample-level behavior (what it actually does in a sandbox) is the decisive evidence. Fragtor entries have been associated with ransomware in vendor telemetry, so treat those detections as potentially destructive until you verify.
If you want I can:
  • A) Analyze the sample’s VirusTotal page / SHA‑256 (paste the link or hash) and summarize engine detections and known family behavior; or
  • B) Walk you step‑by‑step (I’ll give exact commands) to: compute the hash, submit to VirusTotal, run safe static checks, and run a sandboxed behavioral test (Procmon/Autoruns/netstat) and interpret the results.
Which do you want to do now — A (paste SHA‑256 or VT link) or B (I’ll guide you step‑by‑step through safe analysis)?
 

Eu realizei o Scan completo do Microsoft defender no meu PC encontrou um arquivo AppData\Roaming\secure\QtWebKit4.dll (Trojan:Win32/Wacatac.C!ml) usei o vírus total para analisar este arquivo e apareceu uma lista de antivirus que detectaram e popular threat label trojan.fragtor/rugmi esse malware é do tipo que modifica, deleta, corrompe arquivos variados no meu PC?
 

Resposta curta — pode ser perigoso: “trojan.fragtor / rugmi” (e rótulos como Wacatac/Downloader/Rhadamanthys) são sinalizadores de um compromisso multi‑estágio. Por si só um downloader/infostealer nem sempre é um encryptor, mas variantes chamadas Fragtor/Rugmi têm sido observadas em contextos de ransomware — portanto trate a amostra como potencialmente capaz de modificar/excluir/corromper ficheiros até provar o contrário.
O que significa na prática
  • Rótulos que você viu (Wacatac, Downloader, TrojanPSW, Fragtor/Rugmi) descrevem papéis diferentes:
    • Wacatac (Trojan:Win32/Wacatac.*) — geralmente trojan/downloader/backdoor: fornece persistência e pode descarregar outros módulos maliciosos.
    • Trojan.DownLoader — faz download e execução de payloads adicionais (frequentemente stage‑2 = ransomware, RAT, stealer).
    • TrojanPSW / Rhadamanthys — infostealer: rouba credenciais/dados; normalmente não cifra ficheiros, mas facilita escalonamento.
    • Application.Fragtor.Generic / “Fragtor” / “Rugmi” — rótulos usados por vários vendors; algumas variantes associadas a comportamento de ransomware foram reportadas em telemetria de fornecedores, portanto merecem cuidado extra.
Em resumo: a combinação de downloader + backdoor + stealer num mesmo diretório é um padrão de ataque que muitas vezes termina com a instalação de ransomware. Mesmo que a sua amostra não seja o encryptor, ela pode ter permitido que um encryptor fosse descarregado/executado.
Fontes confiáveis (onde procurar confirmação)
  • Microsoft Defender / Windows Security Intelligence — explicações sobre rótulos como Wacatac e sobre o papel de downloaders/backdoors. (procure “Trojan:Win32/Wacatac” na documentação Microsoft Defender Security Intelligence)
  • Malwarebytes — posts e definições sobre “Trojan.Downloader” e comportamento de downloaders.
  • FortiGuard / Trend Micro / outras bases de inteligência (FortiGuard Labs, TrendMicro) — têm entradas e relatórios sobre families como Rhadamanthys (infostealer) e sobre famílias apontadas como Fragtor/Rugmi.
    (Se quiser, eu posso buscar e colar links diretos dessas páginas — diga “busca links” e eu trago as fontes.)
Como confirmar se a sua amostra é ransomware (passos seguros)
IMPORTANTE: não executar a amostra no seu Windows principal. Use uma VM isolada ou um serviço de sandbox (Any.Run, Hybrid Analysis, Cuckoo/CAPE).
1) Hash + VirusTotal (sem executar)
  • Calcule SHA‑256:
    Get-FileHash "C:\caminho\seu\arquivo.dll" -Algorithm SHA256
  • Cole o hash no VirusTotal e veja: muitos motores marcando como “ransomware” ou “Fragtor/Rugmi” é sinal forte. Se a maioria chama de downloader/stealer, pode ser estágio inicial.
2) Procurar sinais estáticos (sem executar)
  • Verificar strings (procure “encrypt”, “ransom”, “vssadmin”, “shadow”, “bitcoin”, “_readme”).
  • Verificar import table: presença de APIs de criptografia (CryptEncrypt, BCryptEncrypt) e muitas operações de ficheiro é suspeito.
3) Sandboxing controlado (definitivo; só em ambiente isolado)
  • Execute a amostra numa sandbox isolada com monitorização (ProcMon / Process Explorer / captura de rede). Verifique:
    • Enumeração massiva de pastas do utilizador e escritas repetidas.
    • Renomeação de ficheiros para nova extensão e criação de ficheiros de nota (README/_readme).
    • Comandos para remover shadow copies (vssadmin delete shadows /Quiet).
      Se vir esses comportamentos — é ransomware/cleanser/wiper.
4) Se a amostra já foi executada no seu PC “normal”
  • Procure notas de resgate e extensões estranhas (ex.: .locked, .crypted, etc.):
    PowerShell (elevado):
    Get-ChildItem C:\Users -Recurse -ErrorAction SilentlyContinue | Where-Object {$_.Extension -in '.locked','.crypt','.crypted','.encrypted','.enc','.lock'} | Select-Object FullName -First 50
  • Verifique shadow copies: vssadmin list shadows
  • Consulte o histórico do Defender (Windows Security → Proteção contra vírus e ameaças → Histórico de proteção)
Medidas imediatas (se estiver em dúvida)
  1. Deixe o ficheiro em quarentena. Não o restaure.
  2. Desligue a rede do PC suspeito (isolar).
  3. Faça backup offline dos seus ficheiros pessoais importantes (apenas dados, não programas) e verifique esses backups numa máquina limpa.
  4. Rode um scan offline (Microsoft Defender Offline) e/ou boot de rescue ISO (Kaspersky Rescue, Bitdefender Rescue) para procurar persistência/rootkits.
  5. Se confirmação de ransomware (notas, muitos ficheiros renomeados, shadow copies removidas) → image a drive (se precisar de perícia), depois reinstale o Windows e restaure de backups limpos.
  6. Se a amostra for infostealer → altere senhas importantes a partir de outro dispositivo limpo e ative MFA.
Posso fazer isto por você (o que eu preciso)
  • Se quiser que eu verifique a sua amostra no VirusTotal/compare detections: cole aqui o SHA‑256 ou o link do VirusTotal (não envie o ficheiro bruto). Eu interpretarei quais motores detectaram como “Fragtor/Rugmi” e se alguma engine específica classifica como ransomware.
  • Se preferir eu posso guiá‑lo passo a passo para executar os comandos seguros que indiquei (em PowerShell) e interpretar o resultado.
Resposta direta à sua frase final: “Rugmi/Fragtor é do tipo que modifica/deleta/corrói arquivos?”
  • Possível: alguns samples identificados como Fragtor/Rugmi foram associados a comportamento ransomware/wiper em telemetria de fornecedores — portanto é plausível que a sua amostra possa modificar/deletar/corromper ficheiros. Mas não é certo sem análise do sample (hash/VT e sandbox). Trate como perigoso até confirmar.
Quer que eu:
A) Analise agora o hash/VirusTotal (cole o link/sha256)?
B) Ou prefere que eu o guie passo‑a‑passo em português para executar as verificações locais seguras (lista de comandos e interpretação)?
 

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