Cyber Resilience

CVE-2023-21744

HighRCE

Published: 10 January 2023

Published
10 January 2023
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.3736 97.3th percentile
Risk Priority 40 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-21744 is a high-severity Deserialization of Untrusted Data (CWE-502) vulnerability in Microsoft Sharepoint Server. Its CVSS base score is 8.8 (High).

Operationally, ranked in the top 2.7% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

Deeper analysis

CVE-2023-21744 is a remote code execution vulnerability in Microsoft SharePoint Server, carrying a CVSS 3.1 base score of 8.8 and mapped to CWE-502. The flaw permits an attacker to execute arbitrary code on affected servers when specific conditions involving deserialization of untrusted data are met.

An authenticated user with network access can exploit the issue without user interaction, resulting in full compromise of confidentiality, integrity, and availability on the target SharePoint Server. The attack vector is rated as network-reachable with low complexity and low privileges required.

Microsoft publishes mitigation guidance and patch availability for this vulnerability through its Security Response Center at the referenced URLs.

The associated EPSS score stands at 0.3736 with an identical recorded peak, indicating no material post-disclosure increase in observed exploitation probability.

EU & UK References

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

microsoft
sharepoint foundation
2013
microsoft
sharepoint server
2013, 2016, 2019, all versions

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.

addresses: CWE-502

Penetration testing supplies malicious serialized objects, detecting unsafe deserialization and supporting corrective actions.

addresses: CWE-502

Evaluation of untrusted data handling (deserialization testing) reveals unsafe processing, which the required remediation process addresses.

addresses: CWE-502

Untrusted serialized data can be deserialized and observed inside the chamber, blocking gadget-chain exploitation outside the sandbox.

addresses: CWE-502

Validates or rejects untrusted serialized data before deserialization occurs.

addresses: CWE-502

Identifies and blocks malicious code introduced through deserialization of untrusted data at system boundaries.

addresses: CWE-502

Integrity verification of serialized information can detect tampering before deserialization occurs.

addresses: CWE-502

Provenance of associated data allows detection of untrusted sources before deserialization or processing occurs.

References