Cyber Resilience

CVE-2025-21295

High

Published: 14 January 2025

Published
14 January 2025
Modified
24 January 2025
KEV Added
Patch
CVSS Score v3.1 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0232 85.2th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-21295 is a high-severity Use After Free (CWE-416) vulnerability in Microsoft Windows 10 1507. Its CVSS base score is 8.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation of Remote Services (T1210); ranked in the top 14.8% 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 SC-7 (Boundary Protection).

Deeper analysis

CVE-2025-21295 is a remote code execution vulnerability in the SPNEGO Extended Negotiation (NEGOEX) Security Mechanism. It is tracked under CWE-416 and carries a CVSS 3.1 base score of 8.1, reflecting network attack vector, high complexity, no required privileges or user interaction, and high impact on confidentiality, integrity, and availability.

An unauthenticated remote attacker can exploit the flaw over the network to achieve arbitrary code execution on the affected system. The attack requires a non-trivial level of complexity but does not depend on any prior authentication or user assistance.

The sole reference points to the Microsoft Security Response Center advisory for CVE-2025-21295, which is the authoritative source for patch availability and mitigation guidance. The associated EPSS score remains low, with a current value of 0.0232 and a peak of 0.0300.

EU & UK References

Vulnerability details

SPNEGO Extended Negotiation (NEGOEX) Security Mechanism 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?

The CVE describes an unauthenticated remote code execution vulnerability in the NEGOEX security mechanism with network attack vector and no user interaction, directly enabling exploitation of remote services.

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

CVEs Like This One

CVE-2025-21296Same product: Microsoft Windows 10 1507
CVE-2025-21406Same product: Microsoft Windows 10 1507
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-2025-53145Same product: Microsoft Windows 10 1507
CVE-2025-21298Same product: Microsoft Windows 10 1507
CVE-2025-47986Same product: Microsoft Windows 10 1507
CVE-2025-21306Same product: Microsoft Windows 10 1507
CVE-2025-21236Same 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 2008
r2
microsoft
windows server 2012
all versions, r2
+5 more product configuration(s) — see NVD for full list

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly remediates the SPNEGO NEGOEX remote code execution vulnerability (CVE-2025-21295) by requiring timely installation of vendor patches as specified in the Microsoft update guide.

prevent

Mitigates remote code execution exploitation of the use-after-free (CWE-416) flaw in NEGOEX by enforcing memory protections like ASLR and DEP to prevent arbitrary code execution.

prevent

Limits network-based exploitation of the unauthenticated remote vulnerability by monitoring and controlling communications at boundaries to restrict access to affected services.

References