Medium September 9, 2026

CVE-2026-77911: Security Advisory

CVE-2026-77911 CVSS 6.5

Who it affects: See the summary below.
What to do: Apply the vendor's update in your next patch window.

CVE-2026-77911 Advisory

Severity: MEDIUM (CVSS 6.5)

Affected Product:

Microsoft Defender Business

Vulnerability Description: Out-of-bounds read in Microsoft Office Word allows unauthorized attackers to disclose information over a network.

KEV Status: Not currently exploited

Remediation: Apply security updates from Microsoft. Refer to the official vulnerability guide: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-77911

Data as of September 9, 2026. Sources: nvd.nist.gov, msrc.microsoft.com. Figures are pulled from public vendor and security data and refreshed automatically.

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