by Kastro
Paper/Archive/CVE-2026-0881

CVE-2026-0881

Mozilla Firefox — Sandbox escape in the Messaging System component

EPSS 0.3%CVSS 10.0
critical.is priorityof 100
36
CVSS 10.0 (ADP)10.0 / 10 × 3030.0Not in CISA KEV+300.0EPSS percentile 28.5.285 × 205.7No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

Sandbox escape in the Messaging System component. This vulnerability was fixed in Firefox 147 and Thunderbird 147.

Affected

ProductAffectedFixed inSource
Firefoxsee advisory147CNA
Thunderbirdsee advisory147CNA
Red Hat Enterprise Linux 10see advisory–redhat-SADP
Red Hat Enterprise Linux 10see advisory–redhat-SADP
Red Hat Enterprise Linux 6see advisory–redhat-SADP
Red Hat Enterprise Linux 7see advisory–redhat-SADP
Red Hat Enterprise Linux 8see advisory–redhat-SADP
Red Hat Enterprise Linux 9see advisory–redhat-SADP

Scores by source

CISA ADP10.0CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
redhat-SADP (CNA)7.5CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refbugzilla.mozilla.org/show_bug.cgi?id=2005845refmozilla.org/security/advisories/mfsa2026-01refmozilla.org/security/advisories/mfsa2026-04refaccess.redhat.com/security/cve/CVE-2026-0881refbugzilla.redhat.com/show_bug.cgi?id=2428970refsecurity.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-0881.json