Vulnerability · Published Oct 9, 2026 · Assigned by GitHub_M

CVE-2026-107837RIOT: Out-of-Bounds Read in RIOT OS 6LoWPAN SFF Fragment Handling

High 8.2

In plain English

A high-severity out-of-bounds read in RIOT from RIOT-OS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 32% of all known vulnerabilities).

Severity (CVSS 3.1)8.2High

Exploit odds (30 days)0.4%top 68.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

RIOT is an open-source microcontroller operating system designed for Internet of Things devices and other embedded systems. In 2026.07 and earlier, _receive() in sys/net/gnrc/network_layer/sixlowpan/gnrc_sixlowpan.c can route an undersized packet into SFF fragment handling after only a minimal payload check. The code then interprets the packet as a sixlowpan_frag_t or larger fragment header without verifying that the packet snip contains the required bytes. A remote attacker can send a malformed 6LoWPAN fragment that causes gnrc_sixlowpan_frag_recv() to read beyond the packet buffer, potentially disclosing memory and crashing the network stack. No fixed repository release is available as of this review.

Affected products (as reported)

Vendor	Product	Versions
RIOT-OS	RIOT	<= 2026.07

Weakness: CWE-125 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H

References

https://github.com/RIOT-OS/RIOT/security/advisories/GHSA-m8mc-q4p7-p8j3 x_refsource_CONFIRM
https://github.com/RIOT-OS/RIOT/pull/22504 x_refsource_MISC
https://github.com/RIOT-OS/RIOT/commit/0cae205cd1d110e0b8fce094714598322d56ce2d x_refsource_MISC