CVE-2026-16412
Memory safety bugs fixed in Firefox ESR 140.13 and Firefox 153
CVSS Score
9.8
EPSS Score
0.3%
EPSS Percentile
25th
Memory safety bugs present in Firefox ESR 140.12 and Firefox 152. 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 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.
| Vendor | mozilla |
| Product | firefox |
| Ecosystems | |
| Industries | Technology |
| Published | Jul 21, 2026 |
| Last Updated | Jul 24, 2026 |
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Affected Versions
Mozilla / Firefox
All versions affected Mozilla / Thunderbird
All versions affected References
bugzilla.mozilla.org: https://bugzilla.mozilla.org/buglist.cgi?bug_id=2005113%2C2025369%2C2026301%2C2028663%2C2029761%2C2042242%2C2043271%2C2043300%2C2044612%2C2045378%2C2045406%2C2045407%2C2045616%2C2045626%2C2045730%2C2045732%2C2045769%2C2045771%2C2047957%2C2048934%2C2049818%2C2049822%2C2050151%2C2050368%2C2051653%2C2051658 bugzilla.mozilla.org: https://bugzilla.mozilla.org/buglist.cgi?bug_id=2043035%2C2045057%2C2045187%2C2045402%2C2045417%2C2045482%2C2045611%2C2045618%2C2045756%2C2046917%2C2047718 bugzilla.mozilla.org: https://bugzilla.mozilla.org/buglist.cgi?bug_id=2045413%2C2053635%2C2053637 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-68/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-70/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-71/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-72/
Credits
Christian Holler, Frederik Braun, Justin Link, Simon Friedberger, Tom Ritter, Tom Schuster and the Mozilla Fuzzing Team