CVE-2026-55040

Microsoft SharePoint Server Security Feature Bypass Vulnerability

CVSS 9.1 critical · Microsoft Microsoft SharePoint Enterprise Server 2016 · published 2026-07-14

Weak authentication in Microsoft Office SharePoint allows an unauthorized attacker to bypass a security feature over a network.

NVD · CVE.org

Coverage 2 sources

1. 2026-08-13 Help Net Security critical Attackers exploit critical SharePoint flaw after PoC goes public (CVE-2026-55040)

   Attackers exploit critical SharePoint flaw CVE-2026-55040 after PoC code is released.

2. 2026-08-18 CISA Cybersecurity Advisories high CISA Adds Four Known Exploited Vulnerabilities to Catalog

   CISA added four new vulnerabilities to its Known Exploited Vulnerabilities Catalog, indicating active exploitation.

Mentioned with

CVE-2026-33824

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