Cyber Resilience

CVE-2025-21342

High

Published: 06 February 2025

Published
06 February 2025
Modified
11 February 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 0.0090 76.2th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-21342 is a high-severity Type Confusion (CWE-843) vulnerability in Microsoft Edge Chromium. 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 23.8% 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 RA-5 (Vulnerability Monitoring and Scanning) and SI-2 (Flaw Remediation).

Deeper analysis

Microsoft Edge (Chromium-based) contains a remote code execution vulnerability tracked as CVE-2025-21342. It carries a CVSS 3.1 base score of 8.8 with the vector AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H and is associated with CWE-843.

An attacker can exploit the flaw over the network without authentication, provided the victim performs some user interaction such as visiting a crafted web page, resulting in full compromise of confidentiality, integrity, and availability on the affected system.

The Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21342 supplies official guidance on available patches and mitigation steps.

EPSS scores remain low, with a current value of 0.0090 and a recorded peak of 0.0138.

EU & UK References

Vulnerability details

Microsoft Edge (Chromium-based) Remote Code Execution Vulnerability

CWE(s)

Related Threats

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.
Why these techniques?

CVE describes RCE in Microsoft Edge browser requiring user interaction over network, directly enabling client-side exploitation (T1203) and user execution via malicious link (T1204.001).

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

CVEs Like This One

CVE-2025-21408Same product: Microsoft Edge Chromium
CVE-2025-21279Same product: Microsoft Edge Chromium
CVE-2026-45495Same product: Microsoft Edge Chromium
CVE-2025-21283Same product: Microsoft Edge Chromium
CVE-2026-41107Same product: Microsoft Edge Chromium
CVE-2026-21223Same product: Microsoft Edge Chromium
CVE-2025-21326Same vendor: Microsoft
CVE-2026-26110Same vendor: Microsoft
CVE-2025-62554Same vendor: Microsoft
CVE-2026-20860Same vendor: Microsoft

Affected Assets

microsoft
edge chromium
≤ 133.0.3065.51

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Requires timely identification, reporting, and correction of flaws like CVE-2025-21342 in Microsoft Edge through vendor patches.

preventdetect

Mandates vulnerability scanning and monitoring to identify and remediate systems affected by the Edge RCE vulnerability CVE-2025-21342.

preventdetect

Deploys malicious code protection mechanisms to block or detect exploits targeting the remote code execution vulnerability in Chromium-based Edge.

References