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CVE-2025-53766 Microsoft CVE debrief

CVE-2025-53766 is a critical Microsoft vulnerability described as a heap-based buffer overflow in Windows GDI+ that can allow remote code execution over a network. The official NVD record assigns CVSS 3.1 9.8 and Microsoft’s advisory provides the affected build floors for Windows and Office branches. Given the no-interaction, network-reachable attack profile, this should be treated as an urgent patching item.

Vendor
Microsoft
Product
Microsoft Office for Android
CVSS
CRITICAL 9.8
CISA KEV
Not listed in stored evidence
Original CVE published
2025-08-12
Original CVE updated
2025-08-14
Advisory published
2025-08-12
Advisory updated
2025-08-14

Who should care

Microsoft Windows and Office administrators, endpoint and vulnerability management teams, and security operators responsible for internet-facing or broadly deployed client/server fleets should prioritize this issue immediately. The supplied NVD CPEs span multiple Windows desktop and server versions as well as Office builds.

Technical summary

The supplied official sources describe a heap-based buffer overflow in Windows GDI+ (CWE-122). NVD lists CVSS 3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H, which indicates a network-reachable flaw that requires no privileges and no user interaction while still carrying potential for full confidentiality, integrity, and availability impact. The NVD CPE criteria show broad Microsoft exposure across multiple Windows and Office branches, and Microsoft’s advisory is the source for the patched build floors.

Defensive priority

Immediate. This is a CVSS 9.8 critical remote code execution issue with broad Microsoft platform coverage and should be prioritized ahead of routine maintenance.

Recommended defensive actions

  • Apply Microsoft’s security update for CVE-2025-53766 using the fixed build levels in the MSRC advisory.
  • Inventory affected Microsoft Windows and Office installations and confirm they are at or above the patched builds listed by Microsoft/NVD for each supported branch.
  • Prioritize externally reachable, high-value, and widely used endpoints and servers first.
  • Monitor for abnormal crashes, memory-corruption indicators, or unexpected code execution attempts on affected Microsoft endpoints during the patch window.
  • If patching is delayed, reduce exposure by limiting access to affected systems and accelerating already-approved compensating controls.

Evidence notes

The supplied corpus includes the official NVD record, the Microsoft Security Response Center advisory, and the CVE record. NVD shows publishedAt 2025-08-12T18:15:45.400Z and modifiedAt 2025-08-14T17:11:06.503Z, with CVSS 3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H and weakness CWE-122. The NVD CPE list covers multiple Microsoft Windows client and server branches plus Office builds. No CISA KEV entry is included in the supplied data.

Official resources

Publicly disclosed in the official CVE/NVD record on 2025-08-12 and updated on 2025-08-14. The supplied enrichment data does not include a CISA KEV entry.