CVE-2026-0881

Sandbox escape in the Messaging System component

Published Jan 13, 2026 CVSS 3.1 · 10 Critical EPSS < 1% KEV · Not listed
Description
Sandbox escape in the Messaging System component. This vulnerability was fixed in Firefox 147 and Thunderbird 147.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Description Sandbox escape in the Messaging System component. This vulnerability affects Firefox < 147 and Thunderbird < 147. Sandbox escape in the Messaging System component. This vulnerability was fixed in Firefox 147 and Thunderbird 147.
Type Values Removed Values Added
First Time appeared Mozilla thunderbird
CPEs cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*
Vendors & Products Mozilla thunderbird
Type Values Removed Values Added
Description Sandbox escape in the Messaging System component. This vulnerability affects Firefox < 147. Sandbox escape in the Messaging System component. This vulnerability affects Firefox < 147 and Thunderbird < 147.
References
Type Values Removed Values Added
First Time appeared Mozilla
Mozilla firefox
Vendors & Products Mozilla
Mozilla firefox
Type Values Removed Values Added
Weaknesses CWE-284
CWE-693
Metrics cvssV3_1

{'score': 10, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Sandbox escape in the Messaging System component. This vulnerability affects Firefox < 147.
Title Sandbox escape in the Messaging System component
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
mozilla
Published
Updated
Jul 15, 2026, 1:23 AM
Reserved
Jan 13, 2026, 1:30 PM
Status
Modified
Published
Jan 13, 2026, 2:16 PM
Modified
Jul 15, 2026, 2:17 AM
Severity
Important
Public date
Jan 13, 2026, 1:30 PM