CVE-2025-21303
Published: 14 January 2025
Summary
CVE-2025-21303 is a high-severity Heap-based Buffer Overflow (CWE-122) vulnerability in Microsoft Windows 10 1507. Its CVSS base score is 8.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Client Execution (T1203); ranked in the top 20.8% 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-16 (Memory Protection) and SI-2 (Flaw Remediation).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Directly addresses the vulnerability by requiring timely remediation through application of vendor patches for the heap-based buffer overflow in Windows Telephony Service.
Implements memory protections like ASLR and DEP that significantly hinder exploitation of heap-based buffer overflows leading to remote code execution.
Requires input validation to mitigate buffer overflows in services processing untrusted network resources or files handled by Windows Telephony Service.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
The CVE describes a remote code execution vulnerability in Windows Telephony Service requiring user interaction with a malicious file or network resource, directly mapping to exploitation of a client application vulnerability for code execution.
NVD Description
Windows Telephony Service Remote Code Execution Vulnerability
Deeper analysisAI
CVE-2025-21303 is a remote code execution vulnerability in the Windows Telephony Service, stemming from a heap-based buffer overflow (CWE-122). Published on January 14, 2025, it carries a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H), indicating high severity due to its potential for network-accessible exploitation with low complexity and no required privileges, though user interaction is necessary.
A remote unauthenticated attacker can exploit this vulnerability by tricking a user into performing a specific action, such as interacting with a maliciously crafted file or network resource handled by the Telephony Service. Successful exploitation allows arbitrary code execution in the context of the service, potentially leading to high-impact compromise of confidentiality, integrity, and availability on the affected Windows system.
Microsoft's Security Response Center provides an update guide for CVE-2025-21303 at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21303, which details available patches and mitigation recommendations for affected Windows versions. Security practitioners should prioritize applying these updates to prevent exploitation.
Details
- CWE(s)