Weak authentication in Microsoft Office SharePoint allows an unauthorized attacker to bypass a security feature over a network.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
None
No disruption
CVSS Vector v3.1
Weakness Type (CWE)
Vulnerable Products 3
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Microsoft Sharepoint_Server
cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:*
|
— |
16.0.19725.20434
|
|
Microsoft Sharepoint_Server
cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:*
|
— | — |
|
Microsoft Sharepoint_Server
cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*
|
— | — |
References 4
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55040
secure@microsoft.com
https://github.com/sfewer-r7/CVE-2026-55040
134c704f-9b21-4f2e-91b3-4a467353bcc0
https://www.rapid7.com/blog/post/ra-microsoft-sharepoint-jwt-token-authenticati…
134c704f-9b21-4f2e-91b3-4a467353bcc0
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026…
134c704f-9b21-4f2e-91b3-4a467353bcc0