CVE-2014-1555: Use-after-free vulnerability in the nsDocLoader::OnProgress function in Mozilla Firefox before 31.0, Firefo...

Security readout for executives and security teams

CVE-2014-1555 is a memory safety flaw in older Mozilla Firefox, Firefox ESR, and Thunderbird releases. A remote attacker could potentially make the application run attacker-controlled code if the vulnerable event path is triggered. The main business risk is legacy systems still running these obsolete versions. Exposure is most likely on unmanaged legacy desktops, old Linux images, frozen VDI/kiosk builds, or servers retaining obsolete Thunderbird or Firefox packages. Current supported Mozilla versions are not identified as affected in the provided sources. Prioritize remediation if any legacy Mozilla products remain in production. The vulnerability is old, but remote code execution in browsers or mail clients is high-impact and usually inexpensive to remove through upgrades. Mitigation focus: Upgrade Firefox to 31.0 or later, or preferably a currently supported release.; Upgrade Firefox ESR 24.x to 24.7 or later if that branch remains in use.; Upgrade Thunderbird to 24.7 or later, preferably a supported current release..

Prepared

Jun 14, 2026, 07:14 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.