Description
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.
Affected products
amazon: freertos-plus-tcp
References3
- aws.amazon.com/security/security-bulletins/AWS-2025-023/ Vendor Advisory
- github.com/FreeRTOS/FreeRTOS-Plus-TCP/security/advisories/GHSA-… Vendor Advisory
- github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.3.4 Release Notes
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L - CVSS 4.0
-
5.3
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 28 · as of 9 November 2026
- CWE
- CWE-476
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.