CVE-2026-81392 Microsoft CVE debrief

Who should care

Defenders and administrators responsible for Microsoft Office Excel installations should assess exposure and apply patches or updates to prevent local information disclosure.

Why it matters

CVE-2026-81392 is a MEDIUM-severity vulnerability in Microsoft Office Excel that allows local information disclosure. Defenders and administrators should assess exposure, apply patches or updates, and monitor for potential attacks.

• Local information disclosure is possible due to the out-of-bounds read vulnerability
• Defenders should verify exposure and apply patches or updates to prevent exploitation
• Inventory and monitoring of Microsoft Office Excel installations are necessary to prevent potential attacks

Technical summary

CVE-2026-81392 is an out-of-bounds read vulnerability in Microsoft Office Excel, allowing local information disclosure. The vulnerability has a CVSS score of 5.5 and is classified as MEDIUM severity. The vulnerability allows unauthorized attackers to disclose information locally. Microsoft Office Excel installations should be assessed for exposure, and patches or updates should be applied to prevent exploitation. The CVE record and NVD entry provide details on the vulnerability. However, specific version information and remediation steps require verification from

Defensive priority

Assess exposure and apply patches for Microsoft Office Excel

Recommended defensive actions

• Inventory Microsoft Office Excel installations for potential exposure
• Apply patches or updates provided by Microsoft
• Monitor for local unauthorized access attempts

Evidence notes

The CVE record and NVD entry provide details on the vulnerability. However, specific version information and remediation steps require verification from official sources.

Sources and 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.