CVE-2023-21742
Published: 10 January 2023
Summary
CVE-2023-21742 is a high-severity Improper Access Control (CWE-284) vulnerability in Microsoft Sharepoint Server. Its CVSS base score is 8.8 (High).
Operationally, ranked in the top 4.9% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
Deeper analysis
Microsoft SharePoint Server is affected by CVE-2023-21742, a remote code execution vulnerability assigned a CVSS 3.1 base score of 8.8. The flaw is categorized under CWE-284 and permits an attacker to run arbitrary code on the server. It was disclosed on 10 January 2023 and impacts on-premises SharePoint deployments.
An authenticated attacker with low privileges can exploit the issue over the network without user interaction. Successful exploitation grants full confidentiality, integrity, and availability impact on the affected server, allowing the attacker to execute code in the context of the SharePoint application.
Microsoft’s Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21742 provides patch information and mitigation guidance for supported SharePoint Server versions.
EPSS for the CVE rose from a lower baseline to a peak of 0.2627 on 2026-04-21 before receding to the current value of 0.1653, indicating a measurable increase in observed exploitation interest after disclosure.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-25909
Vulnerability details
Microsoft SharePoint Server Remote Code Execution Vulnerability
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
The access control policy and procedures directly mandate and enforce proper access control mechanisms across the organization.
Device lock enforces restricted access until re-authentication, directly reducing unauthorized use of active sessions.
Supervision and review of access control activities directly detects and remediates improper access configurations or usages.
Explicitly identifying and documenting actions permitted without identification or authentication enforces proper access control boundaries by defining justified exceptions.
By automatically labeling outputs with security attributes, the control supports attribute-based enforcement and reduces exploitability of improper access control weaknesses.
Associating and retaining security attributes with data directly supports enforcement of access control decisions across storage, processing, and transmission.
Requiring prior authorization for each remote access type prevents improper access control over remote connections.
Requiring authorization of wireless access before allowing connections enforces proper access control for this access method.