Cyber Posture

CVE-2025-21200

High

Published: 11 February 2025

Published
11 February 2025
Modified
28 February 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 0.0016 37.1th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-21200 is a high-severity Heap-based Buffer Overflow (CWE-122) vulnerability in Microsoft Windows Server 2008. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation of Remote Services (T1210); ranked at the 37.1th percentile by exploit likelihood (below the median); 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-16 (Memory Protection).

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 remediates CVE-2025-21200 by requiring timely application of Microsoft patches for the heap-based buffer overflow in Windows Telephony Service.

prevent

Implements memory protections like ASLR and DEP that directly mitigate remote code execution from the heap-based buffer overflow in CVE-2025-21200.

prevent

Requires validation of inputs to the Windows Telephony Service to prevent heap-based buffer overflows exploited in CVE-2025-21200.

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 heap buffer overflow in Windows Telephony Service directly enables exploitation of a remote Windows service to achieve RCE.

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

NVD Description

Windows Telephony Service Remote Code Execution Vulnerability

Deeper analysisAI

CVE-2025-21200 is a Remote Code Execution vulnerability in the Windows Telephony Service. Published on 2025-02-11, 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.

A remote unauthenticated attacker can exploit this vulnerability over the network with low attack complexity, provided they can trick a user into some form of interaction. Successful exploitation enables the attacker to achieve high impacts on confidentiality, integrity, and availability, allowing remote code execution on the affected Windows system.

Microsoft's update guide provides details on mitigations and patches for this vulnerability at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21200.

Details

CWE(s)

Affected Products

microsoft
windows 10 1507
≤ 10.0.10240.20915 · ≤ 10.0.10240.20915
microsoft
windows 10 1607
≤ 10.0.14393.7785 · ≤ 10.0.14393.7785
microsoft
windows 10 1809
≤ 10.0.17763.6893 · ≤ 10.0.17763.6893
microsoft
windows 10 21h2
≤ 10.0.19044.5487
microsoft
windows 10 22h2
≤ 10.0.19045.5487
microsoft
windows 11 22h2
≤ 10.0.22621.4890
microsoft
windows 11 23h2
≤ 10.0.22631.4890
microsoft
windows 11 24h2
≤ 10.0.26100.3194
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-2025-24051Same 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-2025-21250Same product: Microsoft Windows 10 1507
CVE-2025-21252Same product: Microsoft Windows 10 1507
CVE-2025-21248Same product: Microsoft Windows 10 1507
CVE-2025-21417Same product: Microsoft Windows 10 1507

References