Cyber Posture

CVE-2025-1931

High

Published: 04 March 2025

Published
04 March 2025
Modified
13 April 2026
KEV Added
Patch
CVSS Score 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0039 59.8th percentile
Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Description

Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.

Security Summary

CVE-2025-1931 is a use-after-free vulnerability (CWE-416) occurring in the content process side of a WebTransport connection within Mozilla Firefox and Thunderbird products. This flaw enables a potentially exploitable crash and affects versions of Firefox prior to 136, Firefox ESR prior to 115.21 and 128.8, and Thunderbird prior to 136 and 128.8. The issue was publicly disclosed on March 4, 2025.

With a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H), the vulnerability can be exploited remotely over the network by unauthenticated attackers with low complexity and no user interaction required. Successful exploitation leads to a denial-of-service condition through a crash in the browser's content process, which may serve as a foundation for further compromise given its potentially exploitable nature.

Mozilla resolved the vulnerability in Firefox 136, Firefox ESR 115.21, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8. Security practitioners should review Mozilla Security Advisories MFSA 2025-14, MFSA 2025-15, MFSA 2025-16, and MFSA 2025-17, along with Bugzilla entry 1944126, for patch deployment guidance and additional technical details.

Details

CWE(s)
CWE-416

Affected Products

mozilla
firefox
≤ 115.21.0 · ≤ 136.0 · 116.0 — 128.8.0
mozilla
thunderbird
≤ 128.8.0 · 129.0 — 136.0

MITRE ATT&CK Enterprise Techniques

T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
Why these techniques?

UAF in browser content process enables remote crash for DoS via application exploitation (T1499.004) and potentially client-side code execution (T1203) as foundation for further compromise.

Confidence: MEDIUM · MITRE ATT&CK Enterprise v19.0

References