Cyber Resilience

CVE-2025-21248

High

Published: 14 January 2025

Published
14 January 2025
Modified
24 January 2025
KEV Added
Patch
CVSS Score v3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0091 76.3th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-21248 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 23.7% 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).

Deeper analysis

CVE-2025-21248 is a remote code execution vulnerability in the Windows Telephony Service, carrying a CVSS 3.1 score of 8.8. The flaw is associated with CWE-122 and permits an attacker to execute arbitrary code on an affected system when certain conditions are met.

An unauthenticated remote attacker can exploit the issue over the network with low attack complexity and no privileges required, provided the victim performs a user interaction such as visiting a malicious webpage or opening a crafted file. Successful exploitation grants full confidentiality, integrity, and availability impact on the target host.

Microsoft has published guidance for the vulnerability in its Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21248, which includes details on available patches and recommended mitigations. The associated EPSS score remains low, with a current value of 0.0091 and a recorded peak of 0.0121.

EU & UK References

Vulnerability details

Windows Telephony Service Remote Code Execution Vulnerability

CWE(s)

Related Threats

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 enabling arbitrary code execution in Windows Telephony Service directly maps to exploitation of remote services.

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

CVEs Like This One

CVE-2025-21250Same product: Microsoft Windows 10 1507
CVE-2025-21282Same product: Microsoft Windows 10 1507
CVE-2025-21200Same product: Microsoft Windows 10 1507
CVE-2025-21306Same product: Microsoft Windows 10 1507
CVE-2025-21236Same product: Microsoft Windows 10 1507
CVE-2025-21252Same product: Microsoft Windows 10 1507
CVE-2025-24051Same product: Microsoft Windows 10 1507
CVE-2025-21286Same product: Microsoft Windows 10 1507
CVE-2025-21223Same product: Microsoft Windows 10 1507
CVE-2025-21241Same product: Microsoft Windows 10 1507

Affected Assets

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 2016
≤ 10.0.14393.7699
microsoft
windows server 2019
≤ 10.0.17763.6775
+3 more product configuration(s) — see NVD for full list

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Requires identification, reporting, and timely remediation of the heap-based buffer overflow flaw in Windows Telephony Service via patching.

prevent

Mandates validation of untrusted inputs to the Telephony Service to prevent heap buffer overflows from malformed network data requiring user interaction.

prevent

Provides memory protections like ASLR and DEP to hinder successful exploitation of the heap-based buffer overflow for remote code execution.

References