Critical remote code execution in Mozilla Firefox ESR (enterprise release) and mainstream Firefox; widely deployed browser—can enable mass compromise if exploited.
CVE-2026-16412
Memory corruption in Firefox allows remote arbitrary code execution; patched in 153/ESR 140.13.
Is CVE-2026-16412 being exploited?
Not confirmed. CVE-2026-16412 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.52% probability of exploitation in the next 30 days.
How severe is CVE-2026-16412?
CVE-2026-16412 is rated Critical. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-16412?
Yes. A fix has been recorded for CVE-2026-16412. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-16412 affect?
CVE-2026-16412 affects Mozilla Firefox 152, Firefox ESR 140.12, Mozilla Firefox <153, Firefox ESR <140.13. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-16412?
Update Firefox to 153 or ESR to 140.13 immediately.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote arbitrary code execution via memory corruption in Firefox; attacker can execute code as user, deploy malware, steal data, or pivot.
Immediate action required