CVE-2026-0881: Mozilla Firefox · Vulnerability
Affects Mozilla FirefoxSource CVE Database V5
Not known to be exploited · CVSS 10.0 Critical.
Data as of 25 Oct 2026, 19:02 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 28% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 13 Jan 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 2026-10-25.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Mozilla Firefox | Affected
| Fixed in
|
AI-suggested
Mozilla has released official fixes for this vulnerability in Firefox 147 and Thunderbird 147. Users and administrators should update affected products to these versions or later to remediate the issue. No additional mitigations are required beyond applying the official update. Patch status is confirmed by Mozilla advisories MFSA 2026-01 and MFSA 2026-04.
Description
Sandbox escape in the Messaging System component. This vulnerability was fixed in Firefox 147 and Thunderbird 147.
References
- bugzilla.mozilla.org/show_bug.cgi?id=2005845 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-01/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-04/ (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-0881 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2428970 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-0881.json (opens in a new tab)