Vulnerability · Published Mar 24, 2026 · Assigned by mozilla

CVE-2026-4715Uninitialized memory in the Graphics: Canvas2D component

Critical 9.1

In plain English

A critical-severity security flaw 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 39% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)9.1Critical
Exploit odds (30 days)0.4%top 61.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Uninitialized memory in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:10firefox140.9.0-1.el10_1ALSA-2026:5931
AlmaLinux:8firefox140.9.0-1.el8_10.alma.1ALSA-2026:5932
AlmaLinux:9firefox140.9.0-1.el9_7.alma.1ALSA-2026:5930
AlmaLinux:9firefox-x11140.9.0-1.el9_7.alma.1ALSA-2026:5930
AlmaLinux:10thunderbird140.9.0-1.el10_1.alma.1ALSA-2026:6342
AlmaLinux:8thunderbird140.9.0-1.el8_10.alma.1ALSA-2026:6917
AlmaLinux:9thunderbird140.9.0-1.el9_7.alma.1ALSA-2026:6188
Debian:12firefox-esr140.9.0esr-1~deb12u1DSA-6178-1
Debian:12firefox-esr140.9.0esr-1~deb12u1DEBIAN-CVE-2026-4715
Debian:13firefox-esr140.9.0esr-1~deb13u1DEBIAN-CVE-2026-4715
Debian:13firefox-esr140.9.0esr-1~deb13u1DSA-6178-1
Debian:14firefox-esr140.9.0esr-1DEBIAN-CVE-2026-4715
Debian:12thunderbird1:140.9.0esr-1~deb12u1DSA-6179-1
Debian:12thunderbird1:140.9.0esr-1~deb12u1DEBIAN-CVE-2026-4715
Debian:13thunderbird1:140.9.0esr-1~deb13u1DEBIAN-CVE-2026-4715
Debian:13thunderbird1:140.9.0esr-1~deb13u1DSA-6179-1
Debian:14thunderbird1:140.9.0esr-1DEBIAN-CVE-2026-4715
Rocky Linux:10firefox0:140.9.0-1.el10_1RLSA-2026:5931
Rocky Linux:8firefox0:140.9.0-1.el8_10RLSA-2026:5932
Rocky Linux:9firefox0:140.9.0-1.el9_7RLSA-2026:5930
Rocky Linux:10thunderbird0:140.9.0-1.el10_1RLSA-2026:6342
Rocky Linux:8thunderbird0:140.9.0-1.el8_10RLSA-2026:6917
Rocky Linux:9thunderbird0:140.9.0-1.el9_7RLSA-2026:6188
Ubuntu:22.04:LTSmozjs102no fix listedUBUNTU-CVE-2026-4715
Ubuntu:24.04:LTSmozjs102no fix listedUBUNTU-CVE-2026-4715
Ubuntu:24.04:LTSmozjs115no fix listedUBUNTU-CVE-2026-4715
Ubuntu:22.04:LTSmozjs78no fix listedUBUNTU-CVE-2026-4715
Ubuntu:22.04:LTSmozjs91no fix listedUBUNTU-CVE-2026-4715
Ubuntu:22.04:LTSthunderbirdno fix listedUBUNTU-CVE-2026-4715

Affected products (as reported)

VendorProductVersions
Mozilla Firefox see references
Mozilla Thunderbird see references

Weakness: CWE-908 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

References