CVE-2026-55040

CRITICAL

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

CVSS v3.1 Score

9.1
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Published: 7/14/2026Modified: 8/19/2026

Related Intelligence (0)

No articles currently reference this CVE.

References (4)

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55040PatchVendor Advisoryhttps://github.com/sfewer-r7/CVE-2026-55040Exploithttps://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-55040ExploitThird Party Advisoryhttps://www.rapid7.com/blog/post/ra-microsoft-sharepoint-jwt-token-authentication-bypass-cve-2026-55040/US Government Resource