Affects widely used Mozilla products (Firefox/Thunderbird); high-severity privilege escalation that merits broad org attention and rapid patching.
CVE-2026-118008
Privilege escalation in DOM Navigation affecting Firefox and Thunderbird.
Is CVE-2026-118008 being exploited?
Not confirmed. CVE-2026-118008 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.
How severe is CVE-2026-118008?
CVE-2026-118008 is rated High with a CVSS score of 8.8. 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-2026-118008?
Yes. A fix has been recorded for CVE-2026-118008. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-118008 affect?
CVE-2026-118008 affects Mozilla Firefox <159, Mozilla Thunderbird <159. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-118008?
Update Firefox and Thunderbird to 159+ immediately.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Privilege escalation via the DOM Navigation component allowing escalation from web content to elevated browser/email client privileges, potentially enabling code execution or sandbox escape.
Immediate action required