PostgreSQL has released a patch for CVE-2025-12817 — a low‑scoring but operationally meaningful authorization bug in the implementation of the CREATE STATISTICS command that allows a table owner to create statistics objects in schemas without checking whether they possess the schema-level CREATE privilege, creating a potential denial‑of‑service (DoS) condition for legitimate CREATE STATISTICS users.
Background
PostgreSQL’s CREATE STATISTICS is a management command used to collect multi-column statistics that the optimizer can use to estimate cardinalities for complex queries. The command historically required appropriate privileges to create objects in a schema; CVE-2025-12817 stems from a missing authorization check that breaks that expectation and allows a table owner to create a statistics object in any schema regardless of the creator’s CREATE privilege on that schema. The immediate practical effect is not remote code execution or data exfiltration, but a denial-of-service scenario where a later, legitimately privileged CREATE STATISTICS for the same object name fails. The vulnerability was disclosed and fixed in the upstream PostgreSQL project in the releases that patch the 13.x–18.x supported branches: fixed builds include PostgreSQL 13.23, 14.20, 15.15, 16.11, 17.7, and 18.1. The advisory assigns a CVSS v3.1 base score of 3.1 (Low).
Why Windows sysadmins and DBAs should care
Although PostgreSQL is cross‑platform, many Windows shops run PostgreSQL for application back ends, developer tooling, or in hybrid architectures that include Linux/containers. Even a “low” CVSS score can translate into real operational headaches in production:
- DoS against routine DBA workflows: If a table owner (often an application schema owner or developer) can create conflicting statistics objects in another schema, automated maintenance jobs or scheduled statistics builds run by privileged users may fail unexpectedly.
- Multi‑tenant and hosted environments: In multi‑tenant installations where schemas represent tenants, a tenant owner could unintentionally or maliciously create objects that block tenant-admin operations for other users.
- Supply‑chain and packaging lag: Many organizations rely on distribution packages (MSI, Chocolatey, or vendor bundles). Patch availability in those channels can lag upstream releases, extending the window of exposure.
These operational impacts are precisely why even low‑severity privileges/authorization flaws deserve attention during routine patch cycles.
Technical summary and attack model
The root cause, in plain terms
The CREATE STATISTICS command failed to perform a required authorization check when creating the statistics object in a target schema. As a result, a caller who is a table owner (and therefore allowed to define statistics for the table) could create a statistics object inside
any schema — even schemas where the caller lacked the CREATE privilege. A later CREATE STATISTICS from a user who
does have CREATE on that schema, using the same statistics name, will then be blocked because the name is already taken. This is a canonical
missing authorization issue (CWE‑862).
The vulnerability is not a memory corruption or input‑parsing bug — it’s an access control logic error. The direct consequence is availability impact (DoS on a specific maintenance operation), not confidentiality or integrity loss.
Preconditions and exploitation complexity
- Privileges required: The attacker must be a table owner (a low‑privilege but authenticated database principal). This is a common role for application owners, development accounts, or delegated schema owners.
- Network angle: The bug is reachable via normal SQL sessions; it does not require OS access or special network vectors.
- Exploit complexity: Moderate — the attacker needs to know or guess a target schema and a name to clash with, and to arrange the creation sequence such that the privileged user later attempts the same CREATE STATISTICS name. The exploit is therefore not an automated remote worm; it’s an opportunistic denial of service that can be executed when the attacker has database access.
Because the attack requires an authenticated principal and an operational sequence (create‑then‑block), it depends on attacker preparation and timing rather than a single‑shot remote exploit.
Confirming the facts
The PostgreSQL project advisory explicitly lists affected and fixed version numbers and describes the missing authorization behavior; the National Vulnerability Database (NVD) and multiple commercial vulnerability trackers reflect the same summary, CVSS score, and fixed versions. This cross‑validation confirms the technical claims about scope and impact.
Operational impact: scenarios and examples
Scenario 1 — Shared maintenance user
- A DB maintenance account with CREATE privileges on a maintenance schema regularly runs CREATE STATISTICS job for report optimization.
- A table owner in another schema (or a tenant) creates a statistics object using the same name inside the maintenance schema (exploiting the missing check).
- The maintenance job fails on future runs with “object already exists” or name conflict errors; automated monitoring detects the job failure as an availability incident.
Scenario 2 — multi‑tenant hosting
- Tenants are separated by schema; tenant owners have table‑owner privileges inside their schema.
- A tenant owner improperly creates statistics with a name that collides with a name used by tenant‑level automation or by another tenant owner who has legitimate CREATE rights on a shared schema.
- The hosting operator must investigate and either drop the offending statistics object or restore the expected privilege boundaries — a costly operational ticket.
Scenario 3 — automation races
- Infrastructure automation pipelines that create or re-create statistics objects during deployment can fail if a low‑privilege actor creates a conflicting object shortly before automation runs.
- The end result is a deployment rollback or manual intervention, translating into downtime or delayed rollouts.
These examples illustrate that the
value of the bug is operational disruption, not data theft — but operational disruption is still a material risk for production services.
Detection and evidence collection
Detecting exploitation or attempted misuse of CVE‑2025‑12817 requires focusing on unusual CREATE STATISTICS activity and related object‑creation traces.
Key signals to log and monitor:
- Audit logs showing CREATE STATISTICS commands executed by table‑owner roles on schemas where the caller lacks CREATE privilege.
- Errors during scheduled statistics maintenance (failed CREATE STATISTICS due to name conflicts).
- Sudden creation of statistics objects in schemas that are normally write‑protected to the user who created them.
- Alerts for repeated CREATE STATISTICS by the same principal across many schemas in a short time window.
Collect audit records, the exact SQL text, and the session user/role for forensic analysis. If you suspect misuse, preserve WAL segments and object DDL to aid incident investigation and rollback.
Mitigation: immediate, short‑term, and definitive actions
Immediate recommendations (apply within hours)
- Inventory PostgreSQL versions across the estate and identify instances running versions older than the patched releases mentioned above. Use package management and configuration management tools to produce an authoritative list.
- Temporarily restrict CREATE STATISTICS usage to trusted accounts only. Where practicable, limit CREATE/ALTER privileges to a small operations group while you prepare patches.
- Add logging / auditing for CREATE STATISTICS, schema object creation, and unexpected DDL operations. This increases detection ability while you remediate.
Short‑term workarounds (if immediate upgrade is impossible)
- Deny the table‑owner role the ability to execute DDL in other schemas by tightening role membership and schema privileges.
- Use role separation: require maintenance operations to run under a dedicated, privileged user and avoid shared scripts that escalate privileges across schemas.
- If you operate a managed environment where multiple tenants share a server, consider isolating tenant workloads onto separate clusters or instances until the fix can be deployed.
These mitigation steps are operational controls to reduce exploit reliability and impact; they are not replacements for the upstream fix. Multiple vendors and advisory sites recommend upgrading to the fixed PostgreSQL builds rather than relying on workarounds for long periods.
Definitive remediation (apply as soon as feasible)
- Upgrade to a patched PostgreSQL release: 13.23, 14.20, 15.15, 16.11, 17.7, or 18.1 (or later). Applying the vendor‑provided fix is the only guaranteed correction of the missing authorization check.
- After upgrade, replay and validate scheduled create‑statistics jobs and any automation that may have been affected, and remove any unauthorized statistics objects that were created by low‑privilege accounts during the exposure window.
Practical upgrade guidance for Windows environments
- For PostgreSQL running on Windows via the official installers or third‑party installers (e.g., EnterpriseDB), map your installed build to the vendor's patched release and obtain the appropriate MSI or in‑place upgrade package.
- For Docker/containers deployed on Windows hosts, update the container image to a patched tag and rotate containers in a staged rollout.
- For cloud or managed PostgreSQL services (including Azure Database for PostgreSQL), consult the managed service provider’s advisory; managed services may already apply the fix on behalf of customers, but you must confirm the patch level and any required maintenance windows.
- Test upgrades in a staging environment that mirrors schema permissions and automation jobs to validate that CREATE STATISTICS jobs behave as expected post‑patch.
- Plan rollback procedures: backups and object‑level scripts to re-create any required statistics objects should be prepared before large‑scale upgrades.
Detection playbook and triage steps
- Run a targeted search in database audit logs for CREATE STATISTICS commands executed by roles that are not schema creators for the target schema.
- For each suspicious CREATE STATISTICS found:
- Record the session user, timestamp, SQL text, and target schema.
- Check whether that object still exists and whether any legitimate CREATE STATISTICS attempts for the same name failed with “already exists” or permission errors.
- If misuse is confirmed, either:
- Drop the offending statistics object where appropriate (after validating no legitimate dependency), or
- Recreate/rename expected statistics objects under an approved, privileged account.
- If exploitation is suspected at scale, escalate to incident response, preserve logs, and isolate the affected instance until fully remediated.
These steps reduce the time to recover operational capability while preserving forensic evidence.
Risk analysis and longer‑term lessons
Strengths of the vendor response
- The PostgreSQL project rapidly identified and fixed the issue across supported branches, publishing clear fixed version numbers and an advisory summarizing the root cause — a model example of transparent, actionable disclosure for open source infrastructure.
- Multiple independent trackers (NVD, OSV, commercial scanners) quickly indexed the advisory and aligned on the severity and impact, helping administrators prioritize remediation.
Residual risks and practical caveats
- Package and distro lag: Some packaging channels and third‑party distributions take time to ship patched builds; operators relying on those packages must validate the upstream fix has been backported. Distribution metadata is the single most common source of confusion during windows of exposure.
- Operational complexity: The vulnerability’s exploitability depends on application‑level privileges and naming conventions; automated configuration and CI pipelines can inadvertently create the name collisions that make an attack effective.
- False sense of safety from ‘low’ CVSS: Labeling this CVE as Low reflects the limited confidentiality/integrity impact, but it doesn’t diminish its potential to cause operational outages. Treat “low” CVSS with the appropriate operational context — systems that rely on high availability can still be disrupted.
Broader engineering lesson
Authorization checks are easy to overlook when code paths perform object creation under mixed privilege contexts. The fix reinforces a principle familiar to platform engineers:
always validate actor permissions at the boundary where an action affects a separate security domain (schema/tenant), and preserve least privilege for object creation operations.
Cross‑validation and the evidence picture
The PostgreSQL advisory is the primary authoritative source for this CVE and lists the fixed releases and the core technical summary. NVD and commercial vendors (Tenable, Wiz, OSV) independently report the same vulnerability summary, CVSS vector, affected versions, and remediation recommendations, giving defenders at least two independent confirmations to rely on when planning patches and tests. Public trackers also report low EPSS/exploitability at disclosure, consistent with the requirement that an attacker be an authenticated table owner and orchestrate a name‑collision sequence. Note: while third‑party writeups suggest practical mitigations and highlight the DoS nature of the bug, there are no credible public proofs‑of‑concept demonstrating mass exploitation at disclosure time; this is consistent with the exploitable preconditions and the advisory text. Treat claims of immediate automated exploitation with caution unless they are backed by reproducible PoC code or forensic evidence.
Integration with surrounding risk controls
- Change control and automation: Add a check into CI pipelines that ensure CREATE STATISTICS invocations run under clearly scoped, privileged maintenance accounts rather than ad‑hoc developer accounts.
- RBAC and role hygiene: Periodically audit table‑owner privileges and schema CREATE privileges; minimize cross‑schema ownership and avoid shared super‑privileged service accounts for development teams.
- Configuration management: For hosted providers and third‑party packaging, maintain an inventory that maps installed versions to upstream fixed releases; rely on multiple telemetry sources (package metadata, vendor advisories) rather than a single CVE string to make upgrade decisions.
- Incident readiness: Include this class of authorization issue in tabletop exercises that simulate DoS from within the tenant boundary — exercises that spotlight privilege separation and recovery procedures.
Quick reference (engineer’s checklist)
- Patch list: Confirm PostgreSQL instances are at or above 13.23, 14.20, 15.15, 16.11, 17.7, or 18.1.
- Immediate containment: Restrict CREATE STATISTICS to trusted accounts; tighten schema CREATE privileges.
- Monitoring: Enable auditing of CREATE STATISTICS and DDL; alert on cross‑schema CREATE STATISTICS events.
- Validation: In staging, test scheduled stats jobs post‑upgrade; verify no unexpected name conflicts remain.
- Post‑remediation: Remove any unauthorized statistics objects and document the incident and the path to remediation.
Closing analysis
CVE‑2025‑12817 is a reminder that authorization logic — not just memory safety or input validation — is a core part of database security. The vulnerability’s practical impact is primarily operational: an authenticated table owner can interfere with another user’s ability to create statistics objects in a schema, causing maintenance failures and potential downtime. The fix is straightforward: upgrade to the patched PostgreSQL releases as soon as practicable, harden schema privileges in the interim, and add targeted auditing for CREATE STATISTICS activity.
Enterprise defenders should treat this as an actionable maintenance item: it’s not an emergency that requires instant lateral movement across the estate, but it is important to coordinate patching and access controls to prevent avoidable operational outages. Cross‑checking vendor advisories and vulnerability databases confirms the factual details (affected versions, CVSS, and remediation), and practical mitigations are available while you schedule upgrades. Operational discussion threads and community advisories further emphasize the importance of inventorying non‑default configurations and ensuring that package/import channels have actually delivered the upstream fix; these are useful reads when building a remediation timeline. Practical hardening guides that appear in operator forums also stress the same pattern: privilege separation, logging, and staged upgrades minimize disruption while closing the window of exposure.
In short: patch promptly, restrict CREATE STATISTICS until patched where necessary, and add monitoring to detect misuse — that combination will neutralize the risk posed by CVE‑2025‑12817 while preserving operational continuity.
Source: MSRC
Security Update Guide - Microsoft Security Response Center