Vulnerability · Published Apr 7, 2026 · Assigned by mozilla

CVE-2026-5732Incorrect boundary conditions, integer overflow in the Graphics: Text component

High 8.8

In plain English

A high-severity integer overflow 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 30% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.8High
Exploit odds (30 days)0.4%top 69.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Incorrect boundary conditions, integer overflow in the Graphics: Text component. This vulnerability was fixed in Firefox 149.0.2, Firefox ESR 140.9.1, Thunderbird 149.0.2, and Thunderbird 140.9.1.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:10firefox140.9.1-1.el10_1ALSA-2026:7672
AlmaLinux:8firefox140.9.1-1.el8_10.alma.1ALSA-2026:8052
AlmaLinux:9firefox140.9.1-1.el9_7.alma.1ALSA-2026:7671
AlmaLinux:9firefox-x11140.9.1-1.el9_7.alma.1ALSA-2026:7671
AlmaLinux:10thunderbird140.9.1-1.el10_1.alma.1ALSA-2026:9638
AlmaLinux:8thunderbird140.9.1-1.el8_10.alma.1ALSA-2026:9345
AlmaLinux:9thunderbird140.9.1-1.el9_7.alma.1ALSA-2026:8459
Debian:12firefox-esr140.9.1esr-1~deb12u1DEBIAN-CVE-2026-5732
Debian:13firefox-esr140.9.1esr-1~deb13u1DEBIAN-CVE-2026-5732
Debian:14firefox-esr140.9.1esr-1DEBIAN-CVE-2026-5732
Debian:12thunderbird1:140.9.1esr-1~deb12u1DEBIAN-CVE-2026-5732
Debian:13thunderbird1:140.9.1esr-1~deb13u1DEBIAN-CVE-2026-5732
Debian:14thunderbird1:140.9.1esr-1DEBIAN-CVE-2026-5732
Rocky Linux:10firefox0:140.9.1-1.el10_1RLSA-2026:7672
Rocky Linux:8firefox0:140.9.1-1.el8_10RLSA-2026:8052
Rocky Linux:9firefox0:140.9.1-1.el9_7RLSA-2026:7671
Rocky Linux:10thunderbird0:140.9.1-1.el10_1RLSA-2026:9638
Rocky Linux:8thunderbird0:140.9.1-1.el8_10RLSA-2026:9345
Rocky Linux:9thunderbird0:140.9.1-1.el9_7RLSA-2026:8459
Ubuntu:22.04:LTSmozjs102no fix listedUBUNTU-CVE-2026-5732
Ubuntu:24.04:LTSmozjs102no fix listedUBUNTU-CVE-2026-5732
Ubuntu:24.04:LTSmozjs115no fix listedUBUNTU-CVE-2026-5732
Ubuntu:22.04:LTSmozjs78no fix listedUBUNTU-CVE-2026-5732
Ubuntu:22.04:LTSmozjs91no fix listedUBUNTU-CVE-2026-5732
Ubuntu:22.04:LTSthunderbirdno fix listedUBUNTU-CVE-2026-5732

Affected products (as reported)

VendorProductVersions
Mozilla Firefox see references
Mozilla Thunderbird see references

Weakness: CWE-190 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References