CVE-2026-0881
published 2026-01-13CVE-2026-0881: Sandbox escape in the Messaging System component. This vulnerability was fixed in Firefox 147 and Thunderbird 147.
PriorityP355critical10CVSS 3.1
AVNACLPRNUINSCCHIHAH
EPSS
0.31%
22.6th percentile
Sandbox escape in the Messaging System component. This vulnerability was fixed in Firefox 147 and Thunderbird 147.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | firefox | < firefox 147.0-1 (sid) | firefox 147.0-1 (sid) |
| mozilla | firefox | < 147.0 | 147.0 |
| mozilla | firefox | — | — |
| mozilla | thunderbird | < 147.0 | 147.0 |
CVSS provenance
nvdv3.110.0CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
osv10.0CRITICAL
vendor_debian10.0CRITICAL
vendor_redhat10.0CRITICAL
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Red Hat
firefox: Sandbox escape in the Messaging System component
vendor_redhat·2026-01-13·CVSS 10.0
CVE-2026-0881 [CRITICAL] firefox: Sandbox escape in the Messaging System component
firefox: Sandbox escape in the Messaging System component
Sandbox escape in the Messaging System component. This vulnerability affects Firefox < 147 and Thunderbird < 147.
A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue:
Sandbox escape in the Messaging System component
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Package: firefox (Red Hat Enterprise Linux 10) - Not affected
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Not affected
Package: firefox (Red Hat Enterprise Linux 6) - Not affected
Package: firefox (Red Hat Enterprise Linux 7) - Not affected
Package: firefox (Red Hat Enterprise Linux 8) - Not affected
Package: firefox (
Debian
CVE-2026-0881: firefox - Sandbox escape in the Messaging System component. This vulnerability affects Fir...
vendor_debian·2026·CVSS 10.0
CVE-2026-0881 [CRITICAL] CVE-2026-0881: firefox - Sandbox escape in the Messaging System component. This vulnerability affects Fir...
Sandbox escape in the Messaging System component. This vulnerability affects Firefox < 147 and Thunderbird < 147.
Scope: local
sid: resolved (fixed in 147.0-1)
Mozilla
Mozilla Foundation Security Advisory 2026-01: CVE-2026-0881
vendor_mozilla·CVSS 10.0
CVE-2026-0881 [CRITICAL] Mozilla Foundation Security Advisory 2026-01: CVE-2026-0881
Mozilla Foundation Security Advisory 2026-01
CVE: CVE-2026-0881
Product: Firefox
Impact: moderate
Fixed in: Firefox 147
Mozilla
Mozilla Foundation Security Advisory 2026-04: CVE-2026-0881
vendor_mozilla·CVSS 10.0
CVE-2026-0881 [CRITICAL] Mozilla Foundation Security Advisory 2026-04: CVE-2026-0881
Mozilla Foundation Security Advisory 2026-04
CVE: CVE-2026-0881
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 147
OSV
CVE-2026-0881: Sandbox escape in the Messaging System component
osv·2026-01-13·CVSS 10.0
CVE-2026-0881 [CRITICAL] CVE-2026-0881: Sandbox escape in the Messaging System component
Sandbox escape in the Messaging System component. This vulnerability affects Firefox < 147 and Thunderbird < 147.
GHSA
GHSA-cw2j-6pvw-7g9v: Sandbox escape in the Messaging System component
ghsa_unreviewed·2026-01-13
CVE-2026-0881 [CRITICAL] CWE-284 GHSA-cw2j-6pvw-7g9v: Sandbox escape in the Messaging System component
Sandbox escape in the Messaging System component. This vulnerability affects Firefox < 147.
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2005845https://www.mozilla.org/security/advisories/mfsa2026-01/https://www.mozilla.org/security/advisories/mfsa2026-04/https://access.redhat.com/security/cve/CVE-2026-0881https://bugzilla.redhat.com/show_bug.cgi?id=2428970https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-0881.json
2026-01-13
Published