Vulnerability · Published May 27, 2025 · Assigned by mozilla

CVE-2025-5268Memory safety bugs fixed in Firefox 139, Thunderbird 139, Firefox ESR 128.11, and Thunderbird 128.11

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 0.5% (higher than 44% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.1High
Exploit odds (30 days)0.5%top 56.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Memory safety bugs present in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10. 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 139, Firefox ESR 128.11, Thunderbird 139, and Thunderbird 128.11.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:10firefox128.11.0-1.el10_0ALSA-2025:8341
AlmaLinux:8firefox128.11.0-1.el8_10.alma.1ALSA-2025:8308
AlmaLinux:9firefox128.11.0-1.el9_6.alma.1ALSA-2025:8293
AlmaLinux:9firefox-x11128.11.0-1.el9_6.alma.1ALSA-2025:8293
AlmaLinux:10thunderbird128.11.0-1.el10_0.alma.1ALSA-2025:8608
AlmaLinux:8thunderbird128.11.0-1.el8_10.alma.1ALSA-2025:8756
AlmaLinux:9thunderbird128.11.0-1.el9_6.alma.1ALSA-2025:8607
Debian:12firefox-esr128.11.0esr-1~deb12u1DEBIAN-CVE-2025-5268
Debian:12firefox-esr128.11.0esr-1~deb12u1DSA-5926-1
Debian:13firefox-esr128.11.0esr-1DEBIAN-CVE-2025-5268
Debian:14firefox-esr128.11.0esr-1DEBIAN-CVE-2025-5268
Debian:12thunderbird1:128.11.0esr-1~deb12u1DSA-5932-1
Debian:12thunderbird1:128.11.0esr-1~deb12u1DEBIAN-CVE-2025-5268
Debian:13thunderbird1:128.11.0esr-1DEBIAN-CVE-2025-5268
Debian:14thunderbird1:128.11.0esr-1DEBIAN-CVE-2025-5268
Rocky Linux:10firefox0:128.11.0-1.el10_0RLSA-2025:8341
Rocky Linux:8firefox0:128.11.0-1.el8_10RLSA-2025:8308
Rocky Linux:9firefox0:128.11.0-1.el9_6RLSA-2025:8293
Rocky Linux:10thunderbird0:128.11.0-1.el10_0RLSA-2025:8608
Rocky Linux:8thunderbird0:128.11.0-1.el8_10RLSA-2025:8756
Rocky Linux:9thunderbird0:128.11.0-1.el9_6RLSA-2025:8607
Ubuntu:22.04:LTSmozjs102no fix listedUBUNTU-CVE-2025-5268
Ubuntu:24.04:LTSmozjs102no fix listedUBUNTU-CVE-2025-5268
Ubuntu:24.04:LTSmozjs115no fix listedUBUNTU-CVE-2025-5268
Ubuntu:22.04:LTSmozjs78no fix listedUBUNTU-CVE-2025-5268
Ubuntu:22.04:LTSmozjs91no fix listedUBUNTU-CVE-2025-5268
Ubuntu:22.04:LTSthunderbird1:128.12.0+build1-0ubuntu0.22.04.1UBUNTU-CVE-2025-5268
Ubuntu:22.04:LTSthunderbird1:128.12.0+build1-0ubuntu0.22.04.1USN-7663-1

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