Microsoft’s June update cycle has brought significant security enhancements for Windows and Office users, addressing a total of 66 documented vulnerabilities across multiple product families. This month’s Patch Tuesday, a fixture for IT administrators and security-conscious individuals, stands out not just for the volume of patches released, but for the urgency with which several of the vulnerabilities demand attention—highlighting the ever-present game of cat and mouse between software vendors and cyber adversaries. Delving into the specifics, it becomes apparent why timely updates remain the backbone of digital risk management for organizations and individuals alike.
Microsoft’s focus for June’s security update is heavily concentrated on its flagship operating system, with 44 of the remedied vulnerabilities spanning Windows 10, Windows 11, and Windows Server editions still eligible for support. It is important to note that Windows 7 and 8.1 have crossed their end-of-support milestones, and as such, are highly vulnerable to emerging threats. For those still running Windows 10, critical consideration must be given to the fact that its end-of-life date is slated for October, which brings the clock closer to a cutoff for any future security updates. Upgrading to Windows 11 24H2 is now, more than ever, not simply a recommendation but an operational necessity for ongoing protection.
The mechanism of attack is classic in its simplicity: a user need only click a specially crafted link. Doing so executes remote code on the victim’s machine—an attack vector especially pernicious given how easily it slips past user skepticism when embedded in phishing emails or malvertising campaigns. Microsoft has extended patches for even the long-supported Windows Server 2008 iterations, underscoring the gravity and breadth of exposure.
The attack scenario here typically involves enticing a user to connect to a malicious SMB server, at which point crafted responses compromise the system and potentially lead to attacker control with full system rights. Microsoft acknowledged the contributions of various IT security firms that helped surface this issue, a testament to the collaborative nature of modern vulnerability disclosure.
In parallel, Microsoft has moved swiftly to close CVE-2025-47966, an EoP vulnerability found in the Power Automate cloud service, also rated as critical. Power Automate, formerly known as Microsoft Flow, powers a vast array of automated business processes across the cloud, making any such flaw particularly high profile. That this was resolved promptly is reassuring, but it also highlights the increasing interconnectedness of traditional endpoint and cloud-based vulnerabilities.
Perhaps most concerning is the revelation that four other vulnerabilities leverage the document preview window as an attack vector. In practical terms, this means an end user could be compromised merely by viewing a malicious document in a file explorer or email client preview pane—without ever opening the file proper. Such “zero-click” vulnerabilities are prized by cybercriminals, as they require minimal user interaction and, by extension, lower barriers to successful exploitation.
The remaining Office vulnerabilities, although not classified as critical, still reside in the high-risk category. In a modern computing landscape where Office macros and embedded content have long served as delivery mechanisms for malware, timely patching remains essential.
A lag in browser patching—particularly given how rapidly Chromium’s vulnerability and exploit landscape evolves—can leave even cautious users exposed. Organizations with managed systems should enable automatic updates wherever possible and monitor for successful deployments to avoid gaps. The browser, after all, is the most commonly attacked application surface in the modern IT environment.
The critical vulnerabilities patched this month demonstrate common attack vectors used by both sophisticated actors and opportunistic cybercriminals. From remote code execution to privilege escalation and domain takeovers, the risks run the gamut. Notably, the ease of exploiting some of these flaws—such as code execution after clicking malicious links, or via file previews—serves as a potent reminder that social engineering and technical vulnerabilities thrive in tandem.
Critical analysis also demands recognition that even with patches issued, exploits against now-public vulnerabilities may yet emerge in the brief interim between disclosure and full customer adoption. Attackers pore through patch notes, comparing them to previous system states to reverse-engineer working exploits. This is why “Patch now” is not simply a mantra, but a strategy for reducing the so-called vulnerability window to its shortest possible interval.
It is also prudent to highlight the challenge of patch transparency: Microsoft’s handling of CVE-2025-32710, where a fix was shipped “silently” before public documentation appeared, is double-edged. While it potentially protects customers from widespread exploitation, it can also muddle the security research community’s ability to assess and communicate risk.
Finally, while the number of vulnerabilities may seem daunting, they are not a sign of declining software quality. Rather, they reflect the vast attack surface and diligent work of security researchers and internal teams continually probing for—and responsibly reporting—weaknesses. The ongoing partnership between Microsoft and the wider security sector deserves attention and, where appropriate, user trust.
Every device left unpatched, every out-of-date browser running on a network, is a potential launch point for exploits—whether opportunistic or advanced. Regular patching, driven by trusted vendor updates and reinforced by internal policy, remains the single most effective means of countering known threats. New exploits arise constantly, but as shown in June’s cycle, so too does the capacity for mitigation—provided users remain vigilant and organizations invest in sustained, timely defense.
The stakes have never been higher, and complacency is the opponent every Patch Tuesday seeks to defeat. As ever, the digital world favors the prepared.
Source: PCWorld Microsoft's June update fixes dozens of Windows and Office security flaws
A Closer Look at Windows Security Vulnerabilities
Microsoft’s focus for June’s security update is heavily concentrated on its flagship operating system, with 44 of the remedied vulnerabilities spanning Windows 10, Windows 11, and Windows Server editions still eligible for support. It is important to note that Windows 7 and 8.1 have crossed their end-of-support milestones, and as such, are highly vulnerable to emerging threats. For those still running Windows 10, critical consideration must be given to the fact that its end-of-life date is slated for October, which brings the clock closer to a cutoff for any future security updates. Upgrading to Windows 11 24H2 is now, more than ever, not simply a recommendation but an operational necessity for ongoing protection.Actively Exploited: CVE-2025-33053
Perhaps the most alarming find within this round of updates is CVE-2025-33053, a zero-day WebDAV and Internet Explorer vulnerability confirmed as under active attack. WebDAV, an older protocol for web-based distributed authoring and versioning, and the lingering presence of Internet Explorer via the MSHTML platform, have proven to be fertile ground for threat actors seeking footholds on Windows systems. The risk here extends across all supported Windows releases due to the persistence of legacy components.The mechanism of attack is classic in its simplicity: a user need only click a specially crafted link. Doing so executes remote code on the victim’s machine—an attack vector especially pernicious given how easily it slips past user skepticism when embedded in phishing emails or malvertising campaigns. Microsoft has extended patches for even the long-supported Windows Server 2008 iterations, underscoring the gravity and breadth of exposure.
Privilege Escalation: CVE-2025-33073
Visible in cybersecurity circles even before its patch, CVE-2025-33073 became publicly known as an Elevation of Privilege (EoP) vulnerability in the Windows SMB client. While not yet documented as actively exploited, the window for threat actors to capitalize on known weaknesses only narrows once their existence is widely publicized.The attack scenario here typically involves enticing a user to connect to a malicious SMB server, at which point crafted responses compromise the system and potentially lead to attacker control with full system rights. Microsoft acknowledged the contributions of various IT security firms that helped surface this issue, a testament to the collaborative nature of modern vulnerability disclosure.
Remote Code Execution and Domain Security
Several Remote Code Execution (RCE) vulnerabilities are also addressed, with varying risk profiles and attack vectors:- CVE-2025-33071: Targets the Kerberos KDC proxy service (KPSSVC) but spares domain controllers, somewhat limiting its potential blast radius yet remaining critical on affected hosts.
- CVE-2025-29828: Concerns Windows Schannel, with an attacker able to exploit the vulnerability by flooding a server with malformed TLS handshake requests (specifically, fragmented "Hello" packets). Publicly documented attacks in this vein have previously been used in large-scale intrusion campaigns, giving this patch particular urgency for server administrators.
- CVE-2025-32710: Quietly addressed by Microsoft in Remote Desktop Services during May, with formal documentation now following suit. This method of patching, while safeguarding systems, raises transparency questions—though the move can be understood in the context of minimizing public alert to a newly fixed but still broadly vulnerable pathway.
Netlogon and Cloud Threats
Administrative access remains a cherished goal for attackers, and vulnerabilities such as CVE-2025-33070 in Windows’ Netlogon feature up the stakes considerably. This EoP bug, should it be exploited in the wild, allows a threat actor to impersonate a domain administrator by sending carefully authored login requests. Given Netlogon’s critical role in authenticating users and computers in Active Directory environments, the ramifications of compromise include total domain takeover—a nightmare scenario for IT departments.In parallel, Microsoft has moved swiftly to close CVE-2025-47966, an EoP vulnerability found in the Power Automate cloud service, also rated as critical. Power Automate, formerly known as Microsoft Flow, powers a vast array of automated business processes across the cloud, making any such flaw particularly high profile. That this was resolved promptly is reassuring, but it also highlights the increasing interconnectedness of traditional endpoint and cloud-based vulnerabilities.
Office Product Family: Dangerous RCE and Critical Flaws
Office users are not spared from threats this update cycle. Eighteen vulnerabilities are patched in various Office products, the bulk being remote code execution flaws. Five are rated critical—most notably, one targeting SharePoint, a stalwart of corporate intranets and collaboration platforms.Perhaps most concerning is the revelation that four other vulnerabilities leverage the document preview window as an attack vector. In practical terms, this means an end user could be compromised merely by viewing a malicious document in a file explorer or email client preview pane—without ever opening the file proper. Such “zero-click” vulnerabilities are prized by cybercriminals, as they require minimal user interaction and, by extension, lower barriers to successful exploitation.
The remaining Office vulnerabilities, although not classified as critical, still reside in the high-risk category. In a modern computing landscape where Office macros and embedded content have long served as delivery mechanisms for malware, timely patching remains essential.
Browser Security: Keeping Edge in Sync
Security for Microsoft Edge, the company’s Chromium-based web browser, also features in June’s updates. Edge now stands at version 137.0.3296.68, based on Chromium 137.0.7151.69. Importantly, Google has already updated Chrome/Chromium to version 137.0.7151.103/104 as of June 10, addressing high-risk browser vulnerabilities. This highlights the need for users to ensure their browsers receive updates as quickly as their operating systems do, as attackers frequently target these entry points with the latest exploit kits.A lag in browser patching—particularly given how rapidly Chromium’s vulnerability and exploit landscape evolves—can leave even cautious users exposed. Organizations with managed systems should enable automatic updates wherever possible and monitor for successful deployments to avoid gaps. The browser, after all, is the most commonly attacked application surface in the modern IT environment.
The Critical Importance of Staying Current
Security maintenance is a non-negotiable requirement in today’s threat landscape. Microsoft’s latest patches contain clear indications of how both legacy components and emerging technologies (from WebDAV to Power Automate) contribute to a complex, ever-evolving risk profile. Product end of support—like the looming cutoff for Windows 10—should be treated as a ticking clock for both home users and enterprise environments.The critical vulnerabilities patched this month demonstrate common attack vectors used by both sophisticated actors and opportunistic cybercriminals. From remote code execution to privilege escalation and domain takeovers, the risks run the gamut. Notably, the ease of exploiting some of these flaws—such as code execution after clicking malicious links, or via file previews—serves as a potent reminder that social engineering and technical vulnerabilities thrive in tandem.
Risks and Recommendations: Action Items for Readers
With such a broad swath of vulnerabilities addressed in both core Windows platforms and the Office family, there are several key recommendations for users and organizations:- Upgrade Immediately: Users of Windows 10, now heading toward end of life, should upgrade to Windows 11 24H2 as soon as possible. Legacy systems like Windows 7 and 8.1 are no longer defensible on modern networks.
- Patch Promptly: Do not delay installing June 2025 security updates—especially those for Windows, Office, and Edge. Organizations should prioritize servers, endpoint devices, and business-critical applications for expedited rollout.
- Monitor Legacy Components: Components such as WebDAV and MSHTML persist in modern Windows releases mainly for backward compatibility. Where possible, disable or tightly control legacy protocols to reduce attack surface.
- Strengthen Browser Hygiene: Ensure browsers (Edge, Chrome, Chromium variants) are set to auto-update and frequently monitor their current version. Encourage users not to delay restarts prompted by browser updates.
- Control SMB Exposure: Minimize direct SMB port exposure to the Internet/SaaS environments and audit network segments for potential vectors.
- Limit Administrative Rights: Restrict domain administration access and empower users with only the permissions they require. Monitor for anomalous and unauthorized use of privileged credentials—especially after patching known EoP flaws.
- Educate Users: Highlight the risks of clicking suspicious links or previewing unknown documents, even within standard email and file management tools.
A Broader Security Lens
This month’s Patch Tuesday cycle is illustrative of hidden dangers lurking in both familiar and obscure corners of Microsoft’s ecosystem. The presence of vulnerabilities in niche areas (Kerberos proxies, Netlogon, Power Automate connectors) alongside more common application and browser issues signals that security teams must maintain vigilance across all layers of modern systems. No single component can be treated as “safe by default” simply due to lack of recent news—past Patch Tuesday cycles demonstrate that legacy functionality often carries outsized risk.Critical analysis also demands recognition that even with patches issued, exploits against now-public vulnerabilities may yet emerge in the brief interim between disclosure and full customer adoption. Attackers pore through patch notes, comparing them to previous system states to reverse-engineer working exploits. This is why “Patch now” is not simply a mantra, but a strategy for reducing the so-called vulnerability window to its shortest possible interval.
It is also prudent to highlight the challenge of patch transparency: Microsoft’s handling of CVE-2025-32710, where a fix was shipped “silently” before public documentation appeared, is double-edged. While it potentially protects customers from widespread exploitation, it can also muddle the security research community’s ability to assess and communicate risk.
Finally, while the number of vulnerabilities may seem daunting, they are not a sign of declining software quality. Rather, they reflect the vast attack surface and diligent work of security researchers and internal teams continually probing for—and responsibly reporting—weaknesses. The ongoing partnership between Microsoft and the wider security sector deserves attention and, where appropriate, user trust.
Looking Ahead: Patch Tuesdays Remain Essential
With the next Patch Tuesday scheduled for July 8, users and administrators have a narrow window in which to close the gaps presented by June’s round of vulnerabilities. As the pace and sophistication of targeted attacks rise, so too does the necessity of proactive defense.Every device left unpatched, every out-of-date browser running on a network, is a potential launch point for exploits—whether opportunistic or advanced. Regular patching, driven by trusted vendor updates and reinforced by internal policy, remains the single most effective means of countering known threats. New exploits arise constantly, but as shown in June’s cycle, so too does the capacity for mitigation—provided users remain vigilant and organizations invest in sustained, timely defense.
The stakes have never been higher, and complacency is the opponent every Patch Tuesday seeks to defeat. As ever, the digital world favors the prepared.
Source: PCWorld Microsoft's June update fixes dozens of Windows and Office security flaws
