CVE-2026-77237
Unprivileged task in FreeRTOS (<11.3.1) can read privileged kernel memory on MPU-enabled ports.
Is CVE-2026-77237 being exploited?
Not confirmed. CVE-2026-77237 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-2026-77237?
CVE-2026-77237 is rated High. 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-2026-77237?
Yes. A fix has been recorded for CVE-2026-77237. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-77237 affect?
CVE-2026-77237 affects FreeRTOS-Kernel < 11.3.1, MPU-enabled ports with configUSE_QUEUE_SETS=1, Embedded/IoT devices running affected FreeRTOS builds. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-77237?
Upgrade FreeRTOS-Kernel to 11.3.1+ and rebuild firmware.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Local unprivileged task can read privileged kernel memory via xQueueAddToSet(), enabling info disclosure and potential privilege escalation.
Patch when possible
- affected>= 7.4.0 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.