Critical severity9.8NVD Advisory· Published Mar 24, 2026· Updated May 22, 2026
CVE-2026-4698
CVE-2026-4698
Description
JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected products
31cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*+ 3 more
- cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*range: <149.0
- cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*range: <115.34.0
- (no CPE)range: <115.34 or <140.9
- (no CPE)range: <149
- Range: <149 or <140.9
- osv-coords26 versionspkg:apk/chainguard/firefoxpkg: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%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%20SP5
< 149.0-r0+ 25 more
- (no CPE)range: < 149.0-r0
- (no CPE)range: < 149.0-r0
- (no CPE)range: < 140.9.0-1.el9_7.alma.1
- (no CPE)range: < 140.9.0-1.el9_7.alma.1
- (no CPE)range: < 140.9.0-1.el9_7.alma.1
- (no CPE)range: < 140.9.0-1.1
- (no CPE)range: < 140.9.0-150200.152.225.1
- (no CPE)range: < 140.9.0-160000.1.1
- (no CPE)range: < 149.0-1.1
- (no CPE)range: < 140.9.0-150200.8.263.1
- (no CPE)range: < 140.9.0-1.1
- (no CPE)range: < 140.9.0-150200.152.225.1
- (no CPE)range: < 140.9.0-150200.152.225.1
- (no CPE)range: < 140.9.0-150200.152.225.1
- (no CPE)range: < 140.9.0-150200.152.225.1
- (no CPE)range: < 140.9.0-150200.152.225.1
- (no CPE)range: < 140.9.0-112.304.2
- (no CPE)range: < 140.9.0-150200.152.225.1
- (no CPE)range: < 140.9.0-150200.152.225.1
- (no CPE)range: < 140.9.0-150200.152.225.1
- (no CPE)range: < 140.9.0-160000.1.1
- (no CPE)range: < 140.9.0-150200.152.225.1
- (no CPE)range: < 140.9.0-150200.152.225.1
- (no CPE)range: < 140.9.0-150200.152.225.1
- (no CPE)range: < 140.9.0-160000.1.1
- (no CPE)range: < 140.9.0-112.304.2
Patches
Vulnerability mechanics
References
6- www.mozilla.org/security/advisories/mfsa2026-20/nvdVendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-21/nvdVendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-22/nvdVendor Advisory
- bugzilla.mozilla.org/show_bug.cginvdPermissions Required
- www.mozilla.org/security/advisories/mfsa2026-23/nvd
- www.mozilla.org/security/advisories/mfsa2026-24/nvd
News mentions
1- ZDI-26-252: Mozilla Firefox IonMonkey Switch Statement Optimization Type Confusion Remote Code Execution VulnerabilityZero Day Initiative · Apr 2, 2026