Input validation error in Firefox ESR - CVE-2026-8091

Vulnerability identifier: #VU130582

CSH Severity: High

CVSS v4: 8.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-8091

CWE-ID: CWE-20

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to execute arbitrary code.

The vulnerability exists due to improper input validation in the Audio/Video: Playback component when processing media content. A remote attacker can supply specially crafted media content to execute arbitrary code.

User interaction is required to visit a specially crafted website or open a specially crafted URL.

Firefox ESR
SUSE Linux Enterprise Server 15 SP6
SUSE Linux Enterprise Server 15 SP5
SUSE Linux Enterprise Server 15 SP4
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise High Performance Computing LTSS 15
SUSE Linux Enterprise High Performance Computing 15
SUSE Linux Enterprise High Performance Computing ESPOS 15
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Real Time 15
Anolis OS
Desktop Applications Module
openEuler
firefox
firefox-debuginfo
firefox-debugsource
MozillaFirefox
MozillaFirefox-devel
MozillaFirefox-debuginfo
MozillaFirefox-translations-common
MozillaFirefox-debugsource
MozillaFirefox-translations-other
thunderbird

Install security update from vendor's website.

Firefox ESR - addressed in versions 115.35.2, 140.10.2
firefox - addressed in versions 140.10.1-1, 140.10.1-2
firefox-debuginfo - addressed in versions 140.10.1-1, 140.10.1-2
firefox-debugsource - addressed in versions 140.10.1-1, 140.10.1-2
MozillaFirefox - addressed in versions 140.10.2-112.313.1, 140.11.0-150200.152.239.1
MozillaFirefox-devel - addressed in versions 140.10.2-112.313.1, 140.11.0-150200.152.239.1
MozillaFirefox-debuginfo - addressed in versions 140.10.2-112.313.1, 140.11.0-150200.152.239.1
MozillaFirefox-translations-common - addressed in versions 140.10.2-112.313.1, 140.11.0-150200.152.239.1
MozillaFirefox-debugsource - addressed in versions 140.10.2-112.313.1, 140.11.0-150200.152.239.1
MozillaFirefox-translations-other - update to 140.11.0-150200.152.239.1
thunderbird - update to 140.12.0-1.0.1

• https://www.mozilla.org/en-US/security/advisories/mfsa2026-42/
• https://bugzilla.mozilla.org/show_bug.cgi?id=2029301

• Multiple vulnerabilities in Mozilla Firefox
• openEuler 22.03 LTS SP4 update for firefox
• openEuler 24.03 LTS SP3 update for firefox
• openEuler 24.03 LTS SP1 update for firefox
• openEuler 24.03 LTS update for firefox
• SUSE update for MozillaFirefox
• SUSE update for MozillaFirefox
• Anolis OS update for thunderbird