Insufficient Newline Escaping in Firefox's Copy as cURL Feature

CVE-2025-5264

What is CVE-2025-5264?

A security flaw exists in the 'Copy as cURL' feature of Firefox and its Extended Support Release (ESR) versions, where the newline character is not properly escaped. This imperfection can be exploited by an attacker, manipulating the command to facilitate local code execution on the target user's system. Affected versions include Firefox versions below 139 and Firefox ESR versions below 115.24 and 128.11, which may put users at risk without proper mitigation.

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