CVE-2026-55124 Microsoft CVE debrief

Who should care

Organizations using Microsoft Office Word, particularly those with local access to the application, should be aware of this information disclosure vulnerability. IT administrators, security teams, and users of Microsoft Office Word should take necessary precautions to mitigate this vulnerability.

Technical summary

CVE-2026-55124 is an information disclosure vulnerability in Microsoft Office Word due to improper validation of specified types of input. An unauthorized attacker could exploit this vulnerability locally to disclose information. The vulnerability has a CVSS score of 5.5, indicating a medium severity. It is essential for organizations to review and apply the vendor advisory and patch provided by Microsoft to mitigate this vulnerability.

Defensive priority

Medium priority given the local access requirement and the nature of the vulnerability.

Recommended defensive actions

• Review and apply the vendor advisory and patch provided by Microsoft.
• Ensure that all users of Microsoft Office Word are aware of the potential risks and follow best practices for secure document handling.
• Consider implementing compensating controls such as monitoring for suspicious activity related to Microsoft Office Word.
• Review relevant monitoring, detection, and logs for exposed assets that need extra review.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.

Evidence notes

The CVE record and NVD details indicate that this vulnerability allows for local information disclosure. The CVSS score is 5.5, indicating a medium severity. The vulnerability is caused by improper validation of specified types of input in Microsoft Office Word. There is no evidence of public exploitation or widespread impact.

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.