CVE-2025-21363
Published: 14 January 2025
Summary
CVE-2025-21363 is a high-severity Untrusted Pointer Dereference (CWE-822) vulnerability in Microsoft Office Long Term Servicing Channel. Its CVSS base score is 7.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Client Execution (T1203); ranked in the top 17.7% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SI-2 (Flaw Remediation) and SI-3 (Malicious Code Protection).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Timely flaw remediation through vendor patches directly eliminates the untrusted pointer dereference vulnerability in Microsoft Word.
Malicious code protection scans and blocks malicious Word documents exploiting the vulnerability before arbitrary code execution.
Memory protection safeguards prevent unauthorized code execution resulting from untrusted pointer dereferences in malicious documents.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Vulnerability in Microsoft Word client application allows arbitrary code execution upon opening a malicious document, directly enabling T1203 (Exploitation for Client Execution) and T1204.002 (Malicious File under User Execution).
NVD Description
Microsoft Word Remote Code Execution Vulnerability
Deeper analysisAI
CVE-2025-21363 is a remote code execution vulnerability in Microsoft Word. Published on 2025-01-14, it carries a CVSS v3.1 base score of 7.8 (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) and is associated with CWE-822 (Untrusted Pointer Dereference) and NVD-CWE-noinfo.
An attacker can exploit this vulnerability with local access to the target system, low attack complexity, and no required privileges, but it necessitates user interaction such as opening a malicious document. Successful exploitation enables arbitrary code execution on the victim's machine, resulting in high impacts to confidentiality, integrity, and availability.
The Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21363 provides details on patches and mitigation guidance.
Details
- CWE(s)