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TI-2026-83261 Aliases CVE-2026-119086

FreeRTOS-Kernel queue set flaw lets local tasks overwrite kernel stack

Priority LOW 35CWE-121Published · Updated

Key facts

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

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

FreeRTOS-Kernel from 7.4.0 through 11.3.2 is affected on MPU-enabled ports with queue sets enabled. The queue-set selection call xQueueSelectFromSet does not validate the queue-set type, a type confusion flaw (CWE-843). A local unprivileged task can write data past a pointer-sized object on the privileged kernel stack, affecting privileged memory across the MPU isolation boundary. Builds that do not enable queue sets are not affected.

Written with Claude Haiku 5.5 from the sources below · 2026-10-31

Description from the CNA

Missing queue-set type validation in the queue-set selection system call in FreeRTOS-Kernel before V11.3.3 on MPU-enabled ports with queue sets enabled allows a local unprivileged task to write actor-controlled data beyond a pointer-sized object on the privileged kernel stack, affecting privileged memory across the MPU isolation boundary. To remediate this issue, users should upgrade to FreeRTOS-Kernel V11.3.3, rebuild, and reflash affected firmware. Builds that do not enable queue sets are not affected.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00155 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
Partial

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-Kernel7.4.0 – 11.3.2—No fix listedCNA
  • FreeRTOS-Kernel VendorFreeRTOS Affected 7.4.0 – 11.3.2 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 V11.3.3, rebuild, and reflash affected firmware.

Written with Claude Haiku 5.5 from the sources below · 2026-10-31

Timeline

  1. 2026-10-30 Threatist record created from CVE-2026-119086
  2. 2026-10-30 CISA SSVC decision points changed
  3. 2026-10-30 Priority changed: MEDIUM → LOW

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-2026-75383 Numeric truncation in FreeRTOS-Kernel lets tasks access kernel memory CVSS 4.0CRITICAL 9.3
  • 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
See all 11 →

Sources

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