Vulnerability · Published Aug 19, 2025 · Assigned by mozilla

CVE-2025-9184Memory safety bugs fixed in Firefox ESR 140.2, Thunderbird ESR 140.2, Firefox 142 and Thunderbird 142

High 8.1

In plain English

A high-severity memory corruption in Firefox from Mozilla. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 34% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.1High
Exploit odds (30 days)0.4%top 66.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Memory safety bugs present in Firefox ESR 140.1, Thunderbird ESR 140.1, Firefox 141 and Thunderbird 141. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 142, Firefox ESR 140.2, Thunderbird 142, and Thunderbird 140.2.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Ubuntu:22.04:LTSmozjs102no fix listedUBUNTU-CVE-2025-9184
Ubuntu:24.04:LTSmozjs102no fix listedUBUNTU-CVE-2025-9184
Ubuntu:24.04:LTSmozjs115no fix listedUBUNTU-CVE-2025-9184
Ubuntu:22.04:LTSmozjs78no fix listedUBUNTU-CVE-2025-9184
Ubuntu:22.04:LTSmozjs91no fix listedUBUNTU-CVE-2025-9184
Ubuntu:22.04:LTSthunderbird1:140.7.1+build1-0ubuntu0.22.04.1UBUNTU-CVE-2025-9184

Affected products (as reported)

VendorProductVersions
Mozilla Firefox see references
Mozilla Thunderbird see references

Weakness: CWE-119 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

References