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TI-2026-06525 Aliases CVE-2026-7422

MAC Address Validation Bypass in FreeRTOS-Plus-TCP IPv4 and IPv6 Packet Processing

Priority LOW 30CWE-290Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
None · High · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-290.

Summary

Insufficient packet validation in FreeRTOS-Plus-TCP before V4.2.6 and V4.4.1 allows an adjacent network actor to bypass all checksum and minimum-size validation by spoofing the Ethernet source MAC address to match one of the device's own registered endpoints, because the loopback detection mechanism skips all input validation for packets whose source MAC matches a local endpoint. To mitigate this issue, users should upgrade to the fixed version when available.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00177 7th percentileScored 2026-11-07
Fix Fixed FreeRTOS-Plus-TCP (AWS): 4.2.6, 4.4.1

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
AWSFreeRTOS-Plus-TCP4.0.0 to before 4.2.6; 4.3.0 to before 4.4.14.2.6, 4.4.1Patch availableCNA
  • FreeRTOS-Plus-TCP VendorAWS Affected 4.0.0 to before 4.2.6; 4.3.0 to before 4.4.1 Fixed in 4.2.6, 4.4.1 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:amazon:freertos-plus-tcp:*:*:*:*:*:*:*:*4.0.0 to before 4.2.6; 4.3.0 to before 4.4.1VulnerableAWS
  • cpe:2.3:a:amazon:freertos-plus-tcp:*:*:*:*:*:*:*:* Versions 4.0.0 to before 4.2.6; 4.3.0 to before 4.4.1 Vulnerable ·AWS

Remediation

  • Fix · CNA FreeRTOS-Plus-TCP (AWS) Fixed in 4.2.6, 4.4.1

Fixed in the same release

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

  • Advisory ·

    AWS FreeRTOS-Plus-TCP — aws.amazon.com/security/security-bulletins/2026-021-aws

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    • TI-2026-06526 Integer Underflow in ICMP Echo Reply Processing in FreeRTOS-Plus-TCPPriority LOW 26
    Show all 2 records → Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-7422

References

Patch 3

Advisory 1

  • TI-2024-25630 FreeRTOS-Plus-TCP Buffer Over-Read in DNS Response Parser CVSS 3.1CRITICAL 9.6
  • TI-2026-06527 Integer Underflow in DHCPv6 Sub-Option Parser in FreeRTOS-Plus-TCP CVSS 4.0HIGH 7.2
  • TI-2026-06529 Out-of-Bounds Write via Unsanitized Prefix Length in Router Advertisement Processing in FreeRTOS-Plus-TCP CVSS 4.0MEDIUM 6.1
  • TI-2026-06528 Out-of-Bounds Read in Router Advertisement Option Parser in FreeRTOS-Plus-TCP CVSS 4.0MEDIUM 6.0
  • TI-2026-06526 Integer Underflow in ICMP Echo Reply Processing in FreeRTOS-Plus-TCP CVSS 4.0MEDIUM 6.0
  • TI-2025-10648 Invalid Pointer Dereference when receiving UDP/IPv6 packets in FreeRTOS-Plus-TCP CVSS 4.0MEDIUM 5.3
See all 8 →

Sources

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