CVE-2026-77236
Local OOB write in FreeRTOS secure allocation allowing secure-world heap corruption
Is CVE-2026-77236 being exploited?
Not confirmed. CVE-2026-77236 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 0.11% probability of exploitation in the next 30 days.
How severe is CVE-2026-77236?
CVE-2026-77236 is rated High with a CVSS score of 8.3. 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-2026-77236?
Yes. A fix has been recorded for CVE-2026-77236. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-77236 affect?
CVE-2026-77236 affects FreeRTOS-Kernel < 11.3.1, Embedded/IoT devices using FreeRTOS secure-context allocation, Devices implementing secure-world/TrustZone heaps. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-77236?
Upgrade FreeRTOS-Kernel to >=11.3.1 and apply firmware updates to affected devices.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Local attacker can corrupt secure-world heap metadata via an undersized stack parameter OOB write, potentially enabling privilege escalation or arbitrary code execution in secure world.
Patch when possible
- affected>= 10.2.0 and <= 11.3.0
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.