CVE-2026-7424

Summary

Integer underflow in the DHCPv6 sub-option parser in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network actor to corrupt the device's IPv6 address assignment, DNS configuration, and lease times, and to cause a denial of service (permanent IP task freeze requiring hardware reset) by sending a single crafted DHCPv6 packet.

The issue is present whenever DHCPv6 is enabled.

To mitigate this issue, users should upgrade to version V4.2.6 or V4.4.1 or newer.

Affected Software

VendorProductVersion RangeStatus
AWSFreeRTOS-Plus-TCP4.0.0 < 4.2.6affected
AWSFreeRTOS-Plus-TCP4.3.0 < 4.4.1affected
AWSFreeRTOS-Plus-TCP4.2.6unaffected
AWSFreeRTOS-Plus-TCP4.4.1unaffected

Weaknesses

  • CWE-191: CWE-191: Integer Underflow (Wrap or Wraparound)

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

References