Description
Focus incorrectly truncated URLs towards the beginning instead of around the origin. This vulnerability was fixed in Firefox 141.
Affected products
mozilla: firefox; mozilla: thunderbird
References2
- www.mozilla.org/security/advisories/mfsa2025-56/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=1970209 ExploitIssue Tracking
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 38 · as of 8 November 2026
- CWE
- CWE-451
Could this be exploited in your environment?
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