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CVE-2026-72958 Microsoft CVE debrief

A double free vulnerability in Windows Credential Guard allows an authorized attacker to elevate privileges locally. This CVE was published on 2026-09-08T18:20:21.440Z and was last modified on 2026-09-21T15:53:05.120Z. The vulnerability has a CVSS score of 8.2 and is classified as HIGH severity. Defenders responsible for Windows 11 and Windows Server 2025 environments should assess exposure and prioritize verification and remediation efforts. The CVE record and NVD entry provide details on the vulnerability, including its CVSS score of 8.2 and HIGH severity. Microsoft has provided a vendor advisory and patch for this vulnerability.

Vendor
Microsoft
Product
Windows 11 Version 24H2
CVSS
HIGH 8.2
CISA KEV
Not listed in stored evidence
Original CVE published
2026-09-08
Original CVE updated
2026-09-21
Advisory published
2026-09-08
Advisory updated
2026-09-21

Who should care

Defenders responsible for Windows 11 and Windows Server 2025 environments should assess exposure and prioritize verification and remediation efforts.

Why it matters

CVE-2026-72958 is a double free vulnerability in Windows Credential Guard that allows local privilege escalation. Defenders should verify exposure in Windows 11 and Windows Server 2025 environments and prioritize remediation efforts.

  • Local privilege escalation is possible, allowing attackers to gain elevated privileges.
  • Windows 11 and Windows Server 2025 environments are potentially vulnerable.
  • Verification of exposure and application of Microsoft's patch are necessary to prevent exploitation.

Technical summary

The CVE-2026-72958 vulnerability is a double free issue in Windows Credential Guard that allows an authorized attacker to elevate privileges locally. The vulnerability has a CVSS score of 8.2 and is classified as HIGH severity. The vulnerability affects Windows 11 and Windows Server 2025 environments. Defenders should verify exposure in these environments, especially where local privilege escalation is a concern, and apply Microsoft's vendor advisory and patch for this vulnerability.

Defensive priority

Defenders should prioritize verifying exposure in Windows 11 and Windows Server 2025 environments, especially where local privilege escalation is a concern.

Recommended defensive actions

  • Verify exposure in Windows 11 and Windows Server 2025 environments
  • Apply Microsoft's vendor advisory and patch for this vulnerability
  • Monitor local privilege escalation attempts

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, including its CVSS score of 8.2 and HIGH severity. Microsoft has provided a vendor advisory and patch for this vulnerability.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-72958 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-72958

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-72958 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-72958

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.