CVE-2026-102855 Microsoft CVE debrief

Who should care

Defenders responsible for Microsoft Office Visio deployments should assess exposure and apply vendor patches. This includes operators, platform administrators, vulnerability management teams, and security teams who need to prioritize verifying exposure and applying vendor patches to prevent exploitation. Defenders should also review compensating controls for exposed systems while remediation is scheduled and verified

Why it matters

CVE-2026-102855 allows an unauthorized attacker to execute code over a network due to a heap-based buffer overflow in Microsoft Office Visio. Defenders should prioritize verifying exposure and applying vendor patches.

• Verify exposure in Microsoft Office Visio deployments
• Apply vendor patches to prevent exploitation
• Monitor for suspicious activity

Technical summary

A heap-based buffer overflow in Microsoft Office Visio allows an unauthorized attacker to execute code over a network. This vulnerability affects Microsoft Office Visio deployments and has a high CVSS score of 8.8. Defenders should prioritize verifying exposure in Microsoft Office Visio deployments and applying vendor patches to prevent exploitation. The vulnerability has a significant risk to affected systems, and defenders should review compensating controls for exposed systems while remediation is scheduled and verified.

Defensive priority

Defenders should prioritize verifying exposure in Microsoft Office Visio deployments and applying vendor patches.

Recommended defensive actions

• Verify exposure in Microsoft Office Visio deployments
• Apply vendor patches
• Monitor for suspicious activity

Evidence notes

The CVE record and source item provide details on the vulnerability, but limited information is available on exploitation or impact. Defenders should verify exposure in Microsoft Office Visio deployments and apply vendor patches. The CVE record was published on 2026-10-13T18:59:28.303Z and has not been modified since then. There is no information on known or unknown affected scope, but defenders should review the supplied official advisory or CVE record to validate affected scope, and

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.