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TI-2026-75383 Aliases CVE-2026-109588

Numeric truncation in FreeRTOS-Kernel lets tasks access kernel memory

Priority MEDIUM 41CWE-125Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-787 and the CVSS impact.

Summary

FreeRTOS-Kernel versions from 11.3.0 through 11.3.1 on the Arm Cortex-R82 (Armv8-R AArch64) MPU port are affected. Numeric truncation of the buffer length in the MPU buffer authorization check (CWE-197) makes the check validate a smaller window than the real buffer. Under certain conditions, an unprivileged task on MPU-enabled builds can read or write privileged kernel memory beyond the validated window through a stream buffer system call.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00157 4th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
FreeRTOSFreeRTOS-Kernel11.3.0 – 11.3.1—No fix listedCNA
  • FreeRTOS-Kernel VendorFreeRTOS Affected 11.3.0 – 11.3.1 Fixed in — No fix listed CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:amazon:freertos:*:*:*:*:*:*:*:*——AWS
  • cpe:2.3:o:amazon:freertos:*:*:*:*:*:*:*:* Versions — — ·AWS

Remediation

Upgrade FreeRTOS-Kernel to version V11.3.2 or later, as the source description recommends.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    FreeRTOS-Kernel — aws.amazon.com/security/security-bulletins/2026-138-aws

    2 records Highest priority Priority MEDIUM 2 MEDIUM

    Other records, highest priority first

    • TI-2026-75382 Incorrect authorization in FreeRTOS-Kernel Cortex-R82 MPU portPriority MEDIUM 41
    Show all 2 records → Advisory →

Timeline

  1. 2026-10-16 Threatist record created from CVE-2026-109588
  2. 2026-10-18 Priority changed: MEDIUM → LOW
  3. 2026-10-20 CISA SSVC decision points changed
  4. 2026-10-20 Priority changed: LOW → MEDIUM

References

Patch 1

Advisory 2

  • TI-2026-07633 DoS from MQTT v5.0 Deserialization Fault in core MQTT CVSS 4.0HIGH 8.7
  • TI-2024-25630 FreeRTOS-Plus-TCP Buffer Over-Read in DNS Response Parser CVSS 3.1CRITICAL 9.6
  • TI-2026-75384 FreeRTOS-Plus-TCP IPv6 Router Advertisement source verification flaw CVSS 4.0CRITICAL 9.2
  • TI-2026-75382 Incorrect authorization in FreeRTOS-Kernel Cortex-R82 MPU port CVSS 4.0CRITICAL 9.3
  • TI-2026-53921 Improper input validation in FreeRTOS-Kernel timer command handling CVSS 4.0CRITICAL 9.3
  • TI-2024-18695 Privilege Escalation in FreeRTOS Kernel ARMv7-M MPU ports and ARMv8-M ports with MPU support enabled CVSS 3.1HIGH 8.8
See all 11 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences