CVE-2026-55026: Microsoft Office Information Disclosure Vulnerability
Integer overflow or wraparound in Microsoft Office allows an unauthorized attacker to disclose information locally.
CSIRTS triage
- What
- Integer overflow or wraparound in Microsoft Office allows an unauthorized attacker to disclose information locally.
- Who is affected
- Users of Microsoft Office.
- Urgency
- Remediation is necessary as it poses a medium severity risk of information disclosure.
- Action
- Apply the latest security updates for Microsoft Office.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55026
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-2026-550260.41% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 34% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-55026 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
- critical[NEW] [critical] Microsoft Office products: Multiple vulnerabilitiescert-bund
- unknownexploitedNCSC-2026-0237 [1.02] [H/H] Vulnerabilities Fixed in Microsoft Officencsc-nl
- unknownexploitedNCSC-2026-0237 [1.01] [H/H] Vulnerabilities fixed in Microsoft Officencsc-nl
- unknownMultiple vulnerabilities in Microsoft products (July 15, 2026)cert-fr-avis
- unknownMultiple vulnerabilities in Microsoft Office (July 15, 2026)cert-fr-avis
- unknownexploitedNCSC-2026-0237 [1.00] [M/H] Vulnerabilities fixed in Microsoft Officencsc-nl
- mediumCVE-2026-55026: Integer overflow or wraparound in Microsoft Office allows an unauthorized attacker to disclose…nvd
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