Cyber Posture

CVE-2025-21406

High

Published: 11 February 2025

Published
11 February 2025
Modified
14 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-2025-21406 is a high-severity Use After Free (CWE-416) 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-16 (Memory Protection) 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 remediates the Use After Free vulnerability in Windows Telephony Service by requiring timely application of Microsoft patches.

prevent

Implements memory protections such as ASLR and DEP that comprehensively mitigate Use After Free (CWE-416) exploitation leading to remote code execution.

detect

Enables detection of anomalous behavior or remote code execution attempts targeting the Windows Telephony Service over the network.

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?

The CVE describes a remote code execution vulnerability in the Windows Telephony Service that can be exploited over the network, directly mapping to exploitation of remote services for arbitrary code execution.

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

NVD Description

Windows Telephony Service Remote Code Execution Vulnerability

Deeper analysisAI

CVE-2025-21406 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 linked to CWE-416 (Use After Free), with additional NVD-CWE-noinfo classification.

A remote unauthenticated attacker can exploit this vulnerability over the network with low attack complexity, though it requires user interaction. Successful exploitation enables high-impact consequences, including unauthorized access to sensitive data, modification of system integrity, and disruption of availability through arbitrary code execution on the affected Windows system.

Microsoft's update guide provides details on mitigation and patches for CVE-2025-21406 at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21406.

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

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References