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TI-2026-75384 Aliases CVE-2026-102551

FreeRTOS-Plus-TCP IPv6 Router Advertisement source verification flaw

Priority MEDIUM 41CWE-940Published · Updated

Key facts

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

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

Summary

Improper verification of the source of a communication channel in the IPv6 Router Advertisement handler of Amazon FreeRTOS-Plus-TCP before V4.4.2 lets a remote third party influence an endpoint's IPv6 default gateway, on-link prefix and address configuration through a crafted Router Advertisement. The weakness is tracked as CWE-940. CISA's SSVC rates technical impact as total, with exploitation none and automatable no. The CNA rates it CVSS 4.0 9.2 (CRITICAL), and the issue is not in CISA KEV.

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

Description from the CNA

Improper verification of the source of a communication channel in the IPv6 Router Advertisement handler in Amazon FreeRTOS-Plus-TCP before V4.4.2 might allow a remote third-party to influence an endpoint's IPv6 default gateway, on-link prefix, and address configuration via a crafted Router Advertisement. To remediate this issue, users should upgrade to version V4.4.2.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00273 19th 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-Plus-TCPup to 4.4.1—No fix listedCNA
  • FreeRTOS-Plus-TCP VendorFreeRTOS Affected up to 4.4.1 Fixed in — No fix listed CNA

Remediation

Upgrade FreeRTOS-Plus-TCP to version V4.4.2 or later. The affected range is 0 through 4.4.1, and the listed status is no_fix_listed, so check the vendor's advisory for a fix on your branch.

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-Plus-TCP — aws.amazon.com/security/security-bulletins/2026-139-aws

    2 records Highest priority Priority MEDIUM 1 MEDIUM, 1 LOW

    Other records, highest priority first

    • TI-2026-75385 Forged DNS replies can poison the FreeRTOS-Plus-TCP DNS cachePriority LOW 35
    Show all 2 records → Advisory →

Timeline

  1. 2026-10-16 Threatist record created from CVE-2026-102551
  2. 2026-10-18 Priority changed: MEDIUM → LOW
  3. 2026-10-19 CISA SSVC decision points changed
  4. 2026-10-19 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-2026-75383 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
  • 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