Cyber Posture

CVE-2025-21237

High

Published: 14 January 2025

Published
14 January 2025
Modified
29 January 2025
KEV Added
Patch
CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0067 71.4th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-21237 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 of Remote Services (T1210); ranked in the top 28.6% 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-10 (Information Input Validation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploitation of Remote Services (T1210) and 1 other technique. What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly mandates identification, reporting, and timely remediation of flaws such as the heap-based buffer overflow in Windows Telephony Service via patching.

prevent

Provides memory protection mechanisms like ASLR and DEP that mitigate successful exploitation of heap-based buffer overflows leading to RCE.

prevent

Requires validation of information inputs to prevent buffer overflows from malformed data targeting the Windows Telephony Service.

MITRE ATT&CK Enterprise TechniquesAI

T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
Why these techniques?

RCE via remote network exploitation of Windows Telephony Service (buffer overflow) directly maps to T1210 (remote service exploitation) and T1203 (client execution with UI trigger).

Confidence: MEDIUM · MITRE ATT&CK Enterprise v18.1

NVD Description

Windows Telephony Service Remote Code Execution Vulnerability

Deeper analysisAI

CVE-2025-21237 is a Remote Code Execution vulnerability in the Windows Telephony Service, published on 2025-01-14. 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) and is associated with CWE-122 (Heap-based Buffer Overflow) and NVD-CWE-noinfo. The flaw affects the Windows Telephony Service component, enabling attackers to execute arbitrary code on vulnerable systems.

An unauthenticated attacker can exploit this vulnerability remotely over the network with low attack complexity, though it requires user interaction to trigger. Successful exploitation grants high-impact remote code execution, compromising confidentiality, integrity, and availability of the affected system.

Microsoft's Security Response Center (MSRC) provides detailed guidance on mitigation and patching in its update guide at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21237. Security practitioners should consult this advisory for applicable updates to affected Windows versions.

Details

CWE(s)

Affected Products

microsoft
windows 10 1507
≤ 10.0.10240.20890 · ≤ 10.0.10240.20890
microsoft
windows 10 1607
≤ 10.0.14393.7699 · ≤ 10.0.14393.7699
microsoft
windows 10 1809
≤ 10.0.17763.6775 · ≤ 10.0.17763.6775
microsoft
windows 10 21h2
≤ 10.0.19044.5371
microsoft
windows 10 22h2
≤ 10.0.19045.5371
microsoft
windows 11 22h2
≤ 10.0.22621.4751
microsoft
windows 11 23h2
≤ 10.0.22631.4751
microsoft
windows 11 24h2
≤ 10.0.26100.2894
microsoft
windows server 2008
all versions, r2
microsoft
windows server 2012
all versions, r2
+5 more product configuration(s) — see NVD for full list

CVEs Like This One

CVE-2025-21266Same product: Microsoft Windows 10 1507
CVE-2025-21223Same product: Microsoft Windows 10 1507
CVE-2025-21407Same product: Microsoft Windows 10 1507
CVE-2025-21303Same product: Microsoft Windows 10 1507
CVE-2025-21339Same product: Microsoft Windows 10 1507
CVE-2025-21233Same product: Microsoft Windows 10 1507
CVE-2025-21236Same product: Microsoft Windows 10 1507
CVE-2025-21200Same product: Microsoft Windows 10 1507
CVE-2025-21371Same product: Microsoft Windows 10 1507
CVE-2025-24051Same product: Microsoft Windows 10 1507

References