CVE-2023-29357: Microsoft SharePoint Server Privilege Escalation Vulnerability

Microsoft SharePoint Server contains an unspecified vulnerability that allows an unauthenticated attacker, who has gained access to spoofed JWT authentication tokens, to use them for executing a network attack. This attack bypasses authentication, enabling the attacker to gain administrator privileges.

VendorMicrosoft
ProductSharePoint Server
Date added to KEV2024-01-10
Due date (BOD 22-01)2024-01-31
Known ransomware campaign useKnown
CWECWE-303
Required actionApply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

What to do

  1. Identify every instance of Microsoft SharePoint Server in your environment (asset inventory, EDR, vulnerability scanner).
  2. Apply CISA's required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
  3. Federal civilian agencies must act by 2024-01-31 under BOD 22-01; other organizations can use the same date as a target.
  4. Because ransomware use is known, check for signs of compromise and confirm backups are offline and tested.
  5. Check the vendor advisory and NVD entry linked below for affected versions, then record the fix in your change log.

This CVE is flagged by CISA as known to be used in ransomware campaigns. Rehearse your response before you need it: Ransomware tabletop exercise kit (Runbook Foundry).

Sources

Generated from the CISA feed with AI assistance; facts are taken verbatim from the feed. Not affiliated with or endorsed by CISA. Facts come from the CISA Known Exploited Vulnerabilities catalog (public domain).