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: 7/15/2026

Related Intelligence (2)

CRITICALZero Day

Patch Tuesday - July 2026

Microsoft is publishing 622 vulnerabilities on July 2026 Patch Tuesday , including a record-breaking 416 Windows vulnerabilities. Microsoft is aware of exploitation in the wild for two of the vulnerabilities published today, both of which are listed on CISA KEV, as well as public disclosure for one other. As usual, browser vulns are not included in the Patch Tuesday count above. Rapid7 noted last

CVE-2026-55040CVE-2026-56164
Rapid7
CRITICALVulnerability

NVD CRITICAL: CVE-2026-55040 — Weak authentication in Microsoft Office SharePoint allows an unauthorized attack...

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

CVE-2026-55040
NIST NVD

References (1)

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55040PatchVendor Advisory