CVE-2026-27703

RIOT is an open-source microcontroller operating system, designed to match the requirements of Internet of Things (IoT) devices and other embedded devices. In 2026.01 and earlier, the default handler for the well_known_core resource coap_well_known_core_default_handler writes user-provided option data and other data into a fixed size buffer without validating the buffer is large enough to contain the response. This vulnerability allows an attacker to corrupt neighboring stack location, including security-sensitive addresses like the return address, leading to denial of service or arbitrary code execution.

The following products are affected by CVE-2026-27703 vulnerability.

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-27703.

URL	Resource
https://github.com/RIOT-OS/RIOT/security/advisories/GHSA-qgj4-9jff-93cj