What’s Vulnerable › Vulnerabilities

CVE-2026-109588: Numeric truncation in the MPU buffer authorization check in FreeRTOS-Kernel

• Severity: high (CVSS 8.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-10-16 · updated 2026-10-20
• Weakness: CWE-125

Description

Numeric truncation of the buffer length in the MPU buffer authorization check in FreeRTOS-Kernel V11.3.0 and V11.3.1 on the Arm Cortex-R82 (Armv8-R AArch64) MPU port might allow, under certain conditions, an unprivileged task on MPU-enabled builds to read or write privileged kernel memory beyond the validated buffer window, via a stream buffer system call. To remediate this issue, users should upgrade to version V11.3.2 or later.

Affected products

• FreeRTOS-Kernel: from 11.3.0 through 11.3.1

References

• https://aws.amazon.com/security/security-bulletins/2026-138-aws/
• https://github.com/FreeRTOS/FreeRTOS-Kernel/releases/tag/V11.3.2
• https://github.com/FreeRTOS/FreeRTOS-Kernel/security/advisories/GHSA-qf4j-6f5j-876g

Get alerted when CVE-2026-109588 or the next vulnerability affects your stack