CVE-2026-81391: Microsoft Excel Information Disclosure Vulnerability

Details

Source

Microsoft Security Response Center (INTL · vendor-psirt · site)

Severity

medium — CVSS 5.5

Published

2026-09-08

Exploitation

Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-81391

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

• Low exploitation riskCVE-2026-813910.39% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 33% of all EPSS-scored CVEs.

Referenced CVEs

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

• high[NEU] [hoch] Microsoft Office Produkte: Mehrere Schwachstellencert-bund
• mediumCVE-2026-81391: Use of uninitialized resource in Microsoft Office Excel allows an unauthorized attacker to dis…nvd

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