Description
Due to insufficient escaping of the ampersand character in the “Copy as cURL” feature, an attacker could trick a user into using this command, potentially leading to local code execution on the user's system. *This bug only affects Firefox for Windows. Other versions of Firefox are unaffected.*. This vulnerability was fixed in Firefox 139, Firefox ESR 115.24, Firefox ESR 128.11, Thunderbird 139, and Thunderbird 128.11.
Affected products
mozilla: firefox
References6
- www.mozilla.org/security/advisories/mfsa2025-42/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-43/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-44/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=1962301 Permissions Required
- www.mozilla.org/security/advisories/mfsa2025-45/
- www.mozilla.org/security/advisories/mfsa2025-46/
Metrics
- CVSS 3.1
-
4.8
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L - EPSS — exploit probability
- 0% percentile: 11 · as of 7 November 2026
- CWE
- CWE-77
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