Cyber Posture

CVE-2025-21246

High

Published: 14 January 2025

Published
14 January 2025
Modified
24 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-2025-21246 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-10 (Information Input Validation) and SI-2 (Flaw Remediation).

Threat & Defense at a Glance

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

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly mitigates the RCE vulnerability by requiring timely patching of the heap-based buffer overflow in Windows Telephony Service as provided by Microsoft.

prevent

Prevents remote exploitation by validating network inputs to the telephony service, addressing the root causes of heap buffer overflow and out-of-bounds read.

prevent

Mitigates successful heap-based exploits through memory protections that restrict code execution and modifications in privileged memory regions.

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.
Why these techniques?

Remote unauthenticated network exploitation of Windows Telephony Service buffer overflow directly maps to exploitation of remote services for RCE.

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

NVD Description

Windows Telephony Service Remote Code Execution Vulnerability

Deeper analysisAI

CVE-2025-21246 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 linked to CWE-122 (Heap-based Buffer Overflow), CWE-125 (Out-of-bounds Read), and NVD-CWE-noinfo.

Unauthenticated remote attackers can exploit this vulnerability over the network with low attack complexity and no privileges required, though it necessitates user interaction. Successful exploitation enables high-impact effects on confidentiality, integrity, and availability, allowing arbitrary code execution on affected systems.

Microsoft provides mitigation guidance, including patches, in their Security Update Guide at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21246.

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-2025-21223Same product: Microsoft Windows 10 1507
CVE-2025-21236Same product: Microsoft Windows 10 1507
CVE-2025-21200Same product: Microsoft Windows 10 1507
CVE-2025-24051Same product: Microsoft Windows 10 1507
CVE-2025-21282Same product: Microsoft Windows 10 1507
CVE-2025-21306Same product: Microsoft Windows 10 1507
CVE-2025-21286Same product: Microsoft Windows 10 1507
CVE-2025-21245Same product: Microsoft Windows 10 1507
CVE-2025-21250Same product: Microsoft Windows 10 1507
CVE-2025-21252Same product: Microsoft Windows 10 1507

References