CVE-2026-63524: Microsoft Office Information Disclosure Vulnerability

mediumCVSS 5.5CVE-2026-63524

Out-of-bounds read in Microsoft Office allows an unauthorized attacker to disclose information locally.

CSIRTS triage

vendor: Microsoft product: Office Information disclosure Memory corruption

What: An out-of-bounds read in Microsoft Office allows an unauthorized attacker to disclose information locally.
Who is affected: Users opening untrusted Office documents on affected systems.
Urgency: Medium priority; CVSS 5.5 indicates moderate risk and requires local access.
Action: Apply Microsoft security updates for Office when available; avoid opening untrusted Office files.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: medium — CVSS 5.5
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-63524

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-2026-635240.34% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 27% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-63524	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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

Recent advisories for Microsoft Office Information

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

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