CVE-2026-109588
Numeric truncation in the MPU buffer authorization check in FreeRTOS-Kernel
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
9.3
Numeric truncation in the MPU buffer authorization check in FreeRTOS-Kernel
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.
- Record
CVE-2026-109588- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-197, CWE-787, CWE-125
- Updated
- 2026-11-02
EUVDEUVD-2026-102951
9.3
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.
- Record
EUVD-2026-102951- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H - Updated
- 2026-11-02
NVD
9.3
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.
- Record
CVE-2026-109588- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-125, CWE-197, CWE-787
- Updated
- 2026-11-02
OSV
9.3
Numeric truncation in the MPU buffer authorization check in FreeRTOS-Kernel
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.
- Record
CVE-2026-109588- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H - Weakness
- CWE-125, CWE-197, CWE-787
- Updated
- 2026-11-06
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | OSV | |
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-109588 is a critical vulnerability (CVSS 9.3) in Freertos Freertos-kernel, published October 16, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.16%, the 4th percentile. No source names a fixed version.
References
github.com/FreeRTOS/FreeRTOS-Kernel/releases/tag/V11.3.2
aws.amazon.com/security/security-bulletins/2026-138-aws
github.com/FreeRTOS/FreeRTOS-Kernel/security/advisories/GHSA-qf4j-6f5j-876g
github.com/CVEProject/cvelistV5/tree/main/cves/2026/109xxx/CVE-2026-109588.json
nvd.nist.gov/vuln/detail/CVE-2026-109588