CVE-2026-102692
CVE-2026-102692 · RIOT: Potential integer overflow in nanocoap Block2 handling leading to out-of-bounds memory access
This page contains facts from public vulnerability sources. Check the original advisory before updating.
RIOT is an open-source microcontroller operating system designed for Internet of Things devices and other embedded systems. Prior to 2026.07, nanocoap accepts oversized CoAP Block2 option values without enforcing the 20-bit maximum block number, allowing block offset multiplication to overflow on 32-bit targets. The affected master baseline is commit aeeae69e; the verified fix is later on master and remains unreleased. The oversized value passes from coap_get_blockopt() to coap_block_slicer_init(). A remote CoAP client can send a malformed Block2 option that produces an invalid slice range and can cause out-of-bounds memory access, denial of service, or memory corruption. This vulnerability is fixed in 2026.07.
CVSS 9.1 · Critical · EPSS 0.4%
- Published
- Updated
Affected products and versions
riot
- Versions
- < 2026.07: Affected
No fix published
Original sources
- https://github.com/RIOT-OS/RIOT/security/advisories/GHSA-8365-gj33-rgpf
- https://github.com/RIOT-OS/RIOT/commit/6b283ace3565d931b3edff7e115d4f79339253b8
- https://github.com/RIOT-OS/RIOT/commit/ee1fa0ef91874494823d476392572aeefdbc6b74
- https://github.com/RIOT-OS/RIOT/releases/tag/2026.07
- https://nvd.nist.gov/vuln/detail/CVE-2026-102692