CVE-2018-18502: Mozilla developers and community members reported memory safety bugs present in Firefox 64.

Security readout for executives and security teams

Firefox 64 contained memory safety bugs that Mozilla believed could potentially be exploited to run arbitrary code. The documented affected range is Firefox before version 65. There is no supplied evidence of active exploitation, but outdated browsers create meaningful business risk because browser flaws can expose users during normal web activity. Exposure is most likely on endpoints, servers, kiosks, or packaged Linux images still running Firefox 64 or earlier. Ubuntu-managed Firefox installations may be relevant where USN-3874-1 updates were not applied. Current supported Firefox deployments are unlikely to remain exposed if normal browser patching is enforced. Prioritize remediation where Firefox is user-facing or present on managed endpoints. This is an older vulnerability, so urgency depends on whether legacy Firefox remains in use. Treat confirmed Firefox 64 or earlier deployments as high-priority cleanup because the vendor described possible arbitrary code execution. Mitigation focus: Upgrade Firefox to version 65 or later where Firefox is still deployed.; Apply applicable Ubuntu Firefox updates referenced by USN-3874-1.; Remove or replace unsupported Firefox 64 or older installations..

Prepared

Jun 6, 2026, 21:46 UTC (UTC+00:00)

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