CVE-2025-21245
Published: 14 January 2025
Summary
CVE-2025-21245 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 23.8% 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).
Deeper analysis
CVE-2025-21245 is a remote code execution vulnerability affecting the Windows Telephony Service. It carries a CVSS 3.1 base score of 8.8 and is associated with CWE-122 and CWE-125. The flaw permits an unauthenticated remote attacker to execute arbitrary code on affected Windows systems.
Exploitation requires network access and low attack complexity but depends on user interaction. Successful exploitation can result in full compromise of confidentiality, integrity, and availability on the target system without the need for prior authentication.
The official Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21245 addresses patches and mitigation steps for the issue. The associated EPSS score remains low, with a current value of 0.0090 and a recorded peak of 0.0121.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-2312
Vulnerability details
Windows Telephony Service Remote Code Execution Vulnerability
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
RCE via network-accessible Windows service with user interaction directly maps to client-side exploitation and remote service exploitation techniques.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly mitigates CVE-2025-21245 by requiring timely application of Microsoft patches to remediate the heap-based buffer overflow in Windows Telephony Service.
Implements memory protections like ASLR and DEP that directly counter exploitation of heap-based buffer overflows and out-of-bounds reads leading to RCE.
Enforces input validation to the Windows Telephony Service, addressing malformed network inputs that trigger the buffer overflow vulnerability.