Insufficient validation of the prefix length field in IPv6 Router Advertisement processing in FreeRTOS-Plus-TCP before V4.2.6 and V4.4.1 allows an adjacent network actor to cause memory corruption by sending a crafted Router Advertisement with a prefix length value exceeding the maximum valid length, resulting in a heap buffer overflow. Users processing IPv4 RA only are not impacted. To mitigate this issue, users should upgrade to the fixed version when available.

Insufficient option length validation in the IPv6 Router Advertisement parser in FreeRTOS-Plus-TCP before V4.2.6 and V4.4.1 allows an adjacent network actor to cause a denial of service (device crash) by sending a crafted Router Advertisement with a truncated PREFIX_INFORMATION option that is smaller than the expected structure size. To mitigate this issue, users should upgrade to the fixed version when available.

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.

Integer underflow in the ICMP and ICMPv6 echo reply handlers in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network user to cause a denial of service (device crash) when outgoing ping support is enabled, because header sizes are subtracted from a packet length field without validating the field is large enough, resulting in a heap out-of-bounds read of up to approximately 65KB. To mitigate this issue, users should upgrade to the fixed version when available.

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.

A missing validation check in FreeRTOS-Plus-TCP's UDP/IPv6 packet processing code can lead to an invalid pointer dereference when receiving a UDP/IPv6 packet with an incorrect IP version field in the packet header. This issue only affects applications using IPv6. We recommend upgrading to the latest version and ensure any forked or derivative code is patched to incorporate the new fixes.

A missing validation check in FreeRTOS-Plus-TCP's IPv6 packet processing code can lead to an out-of-bounds read when receiving a IPv6 packet with incorrect payload lengths in the packet header. This issue only affects applications using IPv6. We recommend users upgrade to the latest version and ensure any forked or derivative code is patched to incorporate the new fixes.

FreeRTOS-Plus-TCP is a lightweight TCP/IP stack for FreeRTOS. FreeRTOS-Plus-TCP versions 4.0.0 through 4.1.0 contain a buffer over-read issue in the DNS Response Parser when parsing domain names in a DNS response. A carefully crafted DNS response with domain name length value greater than the actual domain name length, could cause the parser to read beyond the DNS response buffer. This issue affects applications using DNS functionality of the FreeRTOS-Plus-TCP stack. Applications that do not use DNS functionality are not affected, even when the DNS functionality is enabled. This vulnerability has been patched in version 4.1.1.