Critical 9.1Published Oct 16, 2026

CVE-2026-102692RIOT: Potential integer overflow in nanocoap Block2 handling leading to out-of-bounds memory access

Updated under an hour ago (2026-10-19 05:00 UTC)

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It affects RIOT-OS RIOT. Add what you run to find out whether that includes you.

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Every CVE for RIOT-OS RIOT

Exploited in the last 30 days

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 (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Weakness (CWE): CWE-190, CWE-787
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Deferred
Record last updated: Oct 16, 2026
First seen by InfoSec Signals: Oct 16, 2026

Affected products

Affected products

RIOT-OS RIOT riot_os:riot (from the name)	before 2026.07	CNA record

References

https://github.com/RIOT-OS/RIOT/security/advisories/GHSA-8365-gj33-rgpfx-refsource-confirm
https://github.com/RIOT-OS/RIOT/commit/6b283ace3565d931b3edff7e115d4f79339253b8x-refsource-misc
https://github.com/RIOT-OS/RIOT/commit/ee1fa0ef91874494823d476392572aeefdbc6b74x-refsource-misc
https://github.com/RIOT-OS/RIOT/releases/tag/2026.07x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.