CVE-2026-55040

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

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

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

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:microsoft:sharepoint_server:::::subscription:::*
	cpe:2.3:a:microsoft:sharepoint_server:2016::::enterprise:::
	cpe:2.3:a:microsoft:sharepoint_server:2019:::::::*

History

No history.

Information

Published : 2026-07-14 18:18

Updated : 2026-08-19 04:17

NVD link : CVE-2026-55040

Mitre link : CVE-2026-55040

CVE.ORG link : CVE-2026-55040

JSON object : View

Products Affected

microsoft

sharepoint_server

CWE

CWE-1390

Weak Authentication

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