Out-of-bounds write in FreeRTOS - CVE-2026-77236
Published: August 25, 2026
Vulnerability identifier: #VU145361
CSH Severity: Low
CVSS v4: 6.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-77236
CWE-ID: CWE-787
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to out-of-bounds write in SecureContext_AllocateContext when allocating a secure context with an undersized stack on ARM TrustZone (ARMv8-M) configurations. A local user can request a secure context with an undersized stack to cause a denial of service.
Only ARM TrustZone (ARMv8-M) configurations that use secure contexts are affected.
Affected software
FreeRTOS
How to mitigate CVE-2026-77236
Install security update from vendor's website.
FreeRTOS - update to 11.3.1