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TI-2026-53921 Aliases CVE-2026-77234

Improper input validation in FreeRTOS-Kernel timer command handling

Priority MEDIUM 41CWE-863Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass
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-863.

Summary

Improper input validation in FreeRTOS-Kernel before 11.3.1 might allow an unprivileged task on MPU-enabled ports to execute code in privileged kernel context. To remediate this issue, users should upgrade to version 11.3.1 or later.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0017 6th 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-Kernel7.0.0 – 11.3.0—No fix listedCNA
  • FreeRTOS-Kernel VendorFreeRTOS Affected 7.0.0 – 11.3.0 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:amazon:freertos:*:*:*:*:*:*:*:*7.0.0 to before 11.3.1VulnerableAWS
  • cpe:2.3:o:amazon:freertos:*:*:*:*:*:*:*:* Versions 7.0.0 to before 11.3.1 Vulnerable ·AWS

Remediation

No fixed version listed by the sources yet.

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/2026-086-aws

    4 records Highest priority Priority MEDIUM 1 MEDIUM, 3 LOW

    Other records, highest priority first

    • TI-2026-53924 Missing type validation in xQueueAddToSet in FreeRTOS-KernelPriority LOW 35
    • TI-2026-53923 Missing size validation in SecureContext_AllocateContext in FreeRTOS-KernelPriority LOW 35
    • TI-2026-53922 Missing privilege check in SecureContext_FreeContext in FreeRTOS-KernelPriority LOW 35
    Show all 4 records → Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-77234

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-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