CVE-2026-21046
TOCTOU in fabricKeymaster trustlet allows local code execution
Is CVE-2026-21046 being exploited?
Not confirmed. CVE-2026-21046 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 0.13% probability of exploitation in the next 30 days.
How severe is CVE-2026-21046?
CVE-2026-21046 is rated High with a CVSS score of 8.4. 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-2026-21046?
Yes. A fix has been recorded for CVE-2026-21046. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-21046 affect?
CVE-2026-21046 affects fabricKeymaster trustlet (TEE/TrustZone) on affected devices, Android devices prior to SMR Jul-2026 Release 1, OEM devices using the affected trustlet. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-21046?
Install SMR Jul-2026 Release 1 and restrict local access until patched.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Local privileged attacker can exploit a TOCTOU race to execute arbitrary code in the trustlet, enabling privilege escalation and potential full device compromise.
Patch when possible