High severity8.1NVD Advisory· Published Jan 13, 2026· Updated Apr 13, 2026
CVE-2026-0891
CVE-2026-0891
Description
Memory safety bugs present in Firefox ESR 140.6, Thunderbird ESR 140.6, Firefox 146 and Thunderbird 146. 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 147, Firefox ESR 140.7, Thunderbird 147, and Thunderbird 140.7.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected products
37cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*+ 3 more
- cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*range: <147.0
- cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*range: <140.7.0
- (no CPE)range: <140.7
- (no CPE)range: <147
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*+ 2 more
- cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*range: <147.0
- cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*range: <140.7.0
- (no CPE)range: <147
- osv-coords30 versionspkg:apk/chainguard/firefoxpkg:apk/chainguard/firefox-esrpkg:apk/wolfi/firefoxpkg:rpm/almalinux/firefoxpkg:rpm/almalinux/firefox-x11pkg:rpm/almalinux/thunderbirdpkg:rpm/opensuse/firefox-esr&distro=openSUSE%20Tumbleweedpkg:rpm/opensuse/MozillaFirefox&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/MozillaFirefox&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/MozillaFirefox&distro=openSUSE%20Tumbleweedpkg:rpm/opensuse/MozillaThunderbird&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/MozillaThunderbird&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/MozillaThunderbird&distro=openSUSE%20Tumbleweedpkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP4-ESPOSpkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP4-LTSSpkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP5-ESPOSpkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP5-LTSSpkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Desktop%20Applications%2015%20SP7pkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20Server%2012%20SP5-LTSSpkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20Server%2015%20SP4-LTSSpkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20Server%2015%20SP5-LTSSpkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20Server%2015%20SP6-LTSSpkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20Server%2016.0pkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20Server%20for%20SAP%20Applications%2015%20SP4pkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20Server%20for%20SAP%20Applications%2015%20SP5pkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20Server%20for%20SAP%20Applications%2015%20SP6pkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20Server%20for%20SAP%20applications%2016.0pkg:rpm/suse/MozillaFirefox&distro=SUSE%20Linux%20Enterprise%20Server%20LTSS%20Extended%20Security%2012%20SP5pkg:rpm/suse/MozillaThunderbird&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Package%20Hub%2015%20SP7pkg:rpm/suse/MozillaThunderbird&distro=SUSE%20Linux%20Enterprise%20Workstation%20Extension%2015%20SP7
< 140.7-r0+ 29 more
- (no CPE)range: < 140.7-r0
- (no CPE)range: < 140.7-r0
- (no CPE)range: < 140.7-r0
- (no CPE)range: < 140.7.0-1.el8_10.alma.1
- (no CPE)range: < 140.7.0-1.el9_7.alma.1
- (no CPE)range: < 140.7.0-1.el9_7.alma.1
- (no CPE)range: < 140.7.0-1.1
- (no CPE)range: < 140.7.0-150200.152.216.1
- (no CPE)range: < 140.7.0-160000.1.1
- (no CPE)range: < 147.0-1.1
- (no CPE)range: < 140.7.0-150200.8.251.1
- (no CPE)range: < 140.8.1-bp160.1.1
- (no CPE)range: < 140.7.0-1.1
- (no CPE)range: < 140.7.0-150200.152.216.1
- (no CPE)range: < 140.7.0-150200.152.216.1
- (no CPE)range: < 140.7.0-150200.152.216.1
- (no CPE)range: < 140.7.0-150200.152.216.1
- (no CPE)range: < 140.7.0-150200.152.216.1
- (no CPE)range: < 140.7.0-112.295.1
- (no CPE)range: < 140.7.0-150200.152.216.1
- (no CPE)range: < 140.7.0-150200.152.216.1
- (no CPE)range: < 140.7.0-150200.152.216.1
- (no CPE)range: < 140.7.0-160000.1.1
- (no CPE)range: < 140.7.0-150200.152.216.1
- (no CPE)range: < 140.7.0-150200.152.216.1
- (no CPE)range: < 140.7.0-150200.152.216.1
- (no CPE)range: < 140.7.0-160000.1.1
- (no CPE)range: < 140.7.0-112.295.1
- (no CPE)range: < 140.7.0-150200.8.251.1
- (no CPE)range: < 140.7.0-150200.8.251.1
Patches
Vulnerability mechanics
References
5- www.mozilla.org/security/advisories/mfsa2026-01/nvdVendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-03/nvdVendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-04/nvdVendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-05/nvdVendor Advisory
- bugzilla.mozilla.org/buglist.cginvdBroken Link
News mentions
0No linked articles in our index yet.