CVE-2023-29357

Microsoft SharePoint Server: Privilege Escalation

As of , CVE-2023-29357 in Microsoft SharePoint Server is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch this week.

Exploited
Yes: CISA listed it on 10 January 2024
US federal deadline
31 January 202421 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Known
EPSS score
0.99Higher than 99% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
EPSS when listed
0.71 on 10 January 2024EPSS on the day CISA listed it.
Public exploit
1 Metasploit module
Fix
Vendor advice: msrc.microsoft.comLinks below, from CISA's entry.

What CISA says to do

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

CISA's required action

What the flaw 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.

CISA's description

Microsoft SharePoint Server Elevation of Privilege Vulnerability

The CVE record's description, from microsoft

CVE published
13 June 2023
Assigned by
microsoft
CVSS
9.8 Critical (CVSS 3.1, from the CNA)
CWE-303
Incorrect Implementation of Authentication Algorithm
CISA SSVC, exploitation
active
CISA SSVC, automatable
yes
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. The US federal deadline to fix it.

Public exploits

Facts from Metasploit's module list and Exploit-DB's index; we never copy exploit code.

  • Metasploit: Sharepoint Dynamic Proxy Generator Unauth RCEexploit module, rank excellent

SharePoint Server: other exploited entries

VulnerabilityProductOur groupListedDeadlineEPSS
CVE-2026-45659Deserialization of Untrusted DataMicrosoft SharePoint ServerPatch nowForensic triage required by CISA; ransomware use, listed within a year0.03
CVE-2026-56164Missing Authentication for Critical FunctionMicrosoft SharePoint ServerPatch nowForensic triage required by CISA0.01
CVE-2023-24955Code InjectionMicrosoft SharePoint ServerPatch this weekRansomware use; Metasploit module; EPSS 0.850.85
CVE-2026-32201Improper Input ValidationMicrosoft SharePoint ServerPatch soon0.43

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