CVE-2026-7424

Description

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.

CVSS Vector

References

• https://aws.amazon.com/security/security-bulletins/2026-022-aws/
• https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.2.6
• https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.4.1
• https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/security/advisories/GHSA-wrhm-c99p-2p8g