Description
Due to insufficient escaping of the newline 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 vulnerability was fixed in Firefox 139, Firefox ESR 115.24, Firefox ESR 128.11, Thunderbird 139, and Thunderbird 128.11.
Affected products
mozilla: firefox
References8
- 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=1950001 Permissions Required
- www.mozilla.org/security/advisories/mfsa2025-45/
- www.mozilla.org/security/advisories/mfsa2025-46/
- lists.debian.org/debian-lts-announce/2025/05/msg00043.html
- lists.debian.org/debian-lts-announce/2025/05/msg00046.html
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: 23 · as of 7 November 2026
- CWE
- CWE-77
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