CVE-2026-2774: Mozilla Firefox · Integer Overflow
Affects Mozilla FirefoxSource CVE Database V5
Not known to be exploited · CVSS 8.8 High.
Data as of 29 Oct 2026, 19:04 UTC
- EPSS
- 0.8% chance of exploitation in 30 days – higher than 58% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 24 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
AI-suggested
Mozilla has released official fixes for this vulnerability in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8. Users and administrators should update to these fixed versions or later to remediate this vulnerability. No additional mitigation is required beyond applying the official updates.
Description
Integer overflow in the Audio/Video component. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.
References
- bugzilla.mozilla.org/show_bug.cgi?id=2014883 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-13/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-14/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-15/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-16/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-17/ (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-2774 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2442290 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-2774.json (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3984 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3976 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:4260 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3361 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3517 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3338 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3515 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3492 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:4432 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3491 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3980 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3495 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3979 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3494 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:4022 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3493 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3983 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:4152 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3978 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3496 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3981 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3497 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3982 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3339 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:3516 (opens in a new tab)