Exploited vulnerability · CISA KEV

Is CVE-2023-29357 exploited? Yes: in CISA KEV since 10 Jan 2024

Gociux · Microsoft SharePoint Server · data: CISA KEV, CVE record, FIRST EPSS

Yes. CVE-2023-29357, Microsoft SharePoint Server Privilege Escalation Vulnerability, is being exploited in the wild. CISA added it to its Known Exploited Vulnerabilities catalog on 10 Jan 2024, 211 days after it was published. It is known to be used in ransomware campaigns. It affects Microsoft SharePoint Server. If you run it, CISA's required action is: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

What it is

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.

What to do

1. Check whether you run it. Look for SharePoint Server in your asset inventory, including appliances and cloud images. Stack check lists every exploited Microsoft CVE at once.
2. Apply the fix. Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
3. If you can't patch today, take the affected service off the internet or restrict who can reach it, and check its logs for signs of compromise since 13 Jun 2023.
4. Get told next time. Email alerts when CISA adds a CVE for Microsoft.

Other exploited CVEs in SharePoint Server

• CVE-2026-56164: Microsoft SharePoint Server Missing Authentication for Critical Function Vulnerability (14 Jul 2026)
• CVE-2026-45659: Microsoft SharePoint Server Deserialization of Untrusted Data Vulnerability (1 Jul 2026)
• CVE-2026-32201: Microsoft SharePoint Server Improper Input Validation Vulnerability (14 Apr 2026)
• CVE-2023-24955: Microsoft SharePoint Server Code Injection Vulnerability (26 Mar 2024)

References

• msrc.microsoft.com/update-guide/vulnerability/CVE-2023-29357
• nvd.nist.gov/vuln/detail/CVE-2023-29357

Sources: CISA KEV (exploitation, ransomware use, required action, due date), the CVE record (publication date, CVSS, CNA), NVD and FIRST EPSS (live score). More: all KEV additions in January 2024 · Microsoft scorecard · act-now radar.