CVE-2026-84135
Critical input-validation flaw in Firefox Focus Android may expose sensitive data.
Is CVE-2026-84135 being exploited?
Not confirmed. CVE-2026-84135 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 0.25% probability of exploitation in the next 30 days.
How severe is CVE-2026-84135?
CVE-2026-84135 is rated Critical with a CVSS score of 9.8. 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-2026-84135?
Yes. A fix has been recorded for CVE-2026-84135. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-84135 affect?
CVE-2026-84135 affects Firefox Focus (Android) < 155, mozilla firefox mobile. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-84135?
Upgrade Firefox Focus on Android to version 155 immediately
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Input-validation/information-exposure flaw allows crafted content to leak sensitive user data and enable follow-on attacks.
Immediate action required