AWS Security Bulletins: CVE-2026-102551 & CVE-2026-102552 - Issue with FreeRTOS-Plus-TCP
AWS Security Bulletins has published a new security advisory. Here is a summary and what to do.
Key points
- New advisory from AWS Security Bulletins.
- Review affected versions in the advisory.
- Apply updates promptly.
AWS Security Bulletins published a security advisory titled “CVE-2026-102551 & CVE-2026-102552 - Issue with FreeRTOS-Plus-TCP”.
At a glance
- Publisher
- AWS Security Bulletins
- CVEs
- CVE-2026-102551, CVE-2026-102552
What the advisory says
Bulletin ID: 2026-139-AWS Scope: AWS Content Type: Important (requires attention) Publication Date: 10/16/2026 10:15 AM PDT Description: FreeRTOS-Plus-TCP is an open-source, thread-safe TCP/IP stack for the FreeRTOS kernel, distributed by Amazon for use on embedded and IoT devices. AWS identified two issues with FreeRTOS-Plus-TCP, affecting multiple versions. CVE-2026-102551: improper verification of the source of a communication channel in the IPv6 Router Advertisement handler. The handler does not fully validate that a received Router Advertisement originates from an on-link source before acting on it. Under certain conditions, a remote third-party might influence an endpoint's IPv6 gateway, prefix, and address configuration, potentially enabling interception of the device's IPv6 traffic. This issue is reachable in the library's default configuration, where ipconfigUSE_IPv6 and ipconfi
What should you do?
- Read the full vendor advisory linked below and confirm whether you run affected versions.
- Schedule the recommended update, prioritising internet-facing systems.
- Watch for exploitation reports; unpatched edge devices are frequent targets.
What to do and how to stay safe: CVE-2026-102551
- Vulnerability severity scores ignore your specific architecture and context.
- Exploitability depends on network exposure and user behavior, not just code flaws.
- Prioritization requires continuous asset inventory and threat intelligence alignment.
Risk-based vulnerability management focuses your limited resources on the flaws that actually threaten your business. Start by mapping your critical assets and checking for active exploits to prioritize your backlog.
Step-by-step guide: Risk-Based Vulnerability Management: Prioritize Fixes by Actual Danger
General security guidance from the Threat Times newsroom. It is not confirmed advice from the organisations named in this story.
