Cyber Posture

CVE-2025-21305

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 0.0122 79.2th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-21305 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 20.8% 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-2 (Flaw Remediation) and SI-16 (Memory Protection).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploitation for Client Execution (T1203) and 2 other techniques. What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly prevents exploitation of CVE-2025-21305 by requiring timely application of vendor patches to the vulnerable Windows Telephony Service.

prevent

Mitigates remote code execution from the heap-based buffer overflow (CWE-122) by enforcing memory protections such as DEP and ASLR to block unauthorized code execution.

preventdetect

Antimalware scanning detects and blocks malicious files or links crafted to trigger the Windows Telephony Service vulnerability.

MITRE ATT&CK Enterprise TechniquesAI

T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1204.001 Malicious Link Execution
An adversary may rely upon a user clicking a malicious link in order to gain execution.
T1204.002 Malicious File Execution
An adversary may rely upon a user opening a malicious file in order to gain execution.
Why these techniques?

RCE vulnerability requires user interaction with malicious link or crafted file to trigger arbitrary code execution on client, directly enabling T1203 (Exploitation for Client Execution) and T1204 subtechniques (User Execution via malicious link/file).

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

NVD Description

Windows Telephony Service Remote Code Execution Vulnerability

Deeper analysisAI

CVE-2025-21305 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 and NVD-CWE-noinfo.

A remote, unauthenticated attacker can exploit this vulnerability by tricking a user into some form of interaction, such as clicking a malicious link or opening a crafted file. Successful exploitation enables arbitrary code execution on the target system, resulting in high impacts to confidentiality, integrity, and availability.

The Microsoft Security Response Center update guide at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21305 provides details on associated advisories and patches for mitigation.

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-2025-21407Same 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-2025-21371Same product: Microsoft Windows 10 1507
CVE-2025-24993Same product: Microsoft Windows 10 1507
CVE-2025-21409Same product: Microsoft Windows 10 1507
CVE-2025-21240Same product: Microsoft Windows 10 1507
CVE-2025-24056Same product: Microsoft Windows 10 1507

References