What’s Vulnerable › Vulnerabilities

CVE-2025-8043: Incorrect URL truncation

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2025-07-22 · updated 2026-09-30
• Weakness: CWE-451

Description

Focus incorrectly truncated URLs towards the beginning instead of around the origin. This vulnerability was fixed in Firefox 141.

Affected products

• Mozilla Firefox: before 141.0 — fixed in 141.0
• Mozilla Thunderbird: before 141.0 — fixed in 141.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 141.0; Mozilla Thunderbird 141.0. Check the vendor advisory for mitigations.

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=1970209
• https://www.mozilla.org/security/advisories/mfsa2025-56/

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