by Kastro
Paper/Archive/CVE-2026-2786

CVE-2026-2786

Mozilla Firefox — Use-after-free in the JavaScript Engine component

EPSS 0.5%CVSS 9.8
critical.is priorityof 100
38
CVSS 9.8 (NVD)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 43.8.438 × 208.8No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

Use-after-free in the JavaScript Engine component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

Affected

ProductAffectedFixed inSource
Firefoxsee advisory140.8CNA
Thunderbirdsee advisory140.8CNA

Scores by source

NVD9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADP8.8CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: no · Technical impact: total

References

refbugzilla.mozilla.org/show_bug.cgi?id=2013612refmozilla.org/security/advisories/mfsa2026-13refmozilla.org/security/advisories/mfsa2026-15refmozilla.org/security/advisories/mfsa2026-16refmozilla.org/security/advisories/mfsa2026-17