FreeRTOS-Plus-TCP DHCPv6 Integer Underflow (V4.4.1/4.2.6)
CVE-2026-7424 Published on April 29, 2026
Integer Underflow in DHCPv6 Sub-Option Parser in FreeRTOS-Plus-TCP
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.
Vulnerability Analysis
Weakness Type
What is an Integer underflow Vulnerability?
The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result. This can happen in signed and unsigned cases.
CVE-2026-7424 has been classified to as an Integer underflow vulnerability or weakness.
Products Associated with CVE-2026-7424
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Affected Versions
AWS FreeRTOS-Plus-TCP:- Version 4.0.0 and below 4.2.6 is affected.
- Version 4.3.0 and below 4.4.1 is affected.
- Version 4.2.6 is unaffected.
- Version 4.4.1 is unaffected.