Out-of-bounds Read in Riot-Os Riot
CVE-2026-25139
RIOT is an open-source microcontroller operating system, designed to match the requirements of Internet of Things (IoT) devices and other embedded devices. In version 2025.10 and prior, multiple out-of-bounds read allow any unauthenticated user, with ability to send or manipulate input packets, to read adjacent memory locations, or crash a vulnerable device running the 6LoWPAN stack. The received packet is cast into a sixlowpan_sfr_rfrag_t struct and dereferenced without validating the packet is large enough to contain the struct object. At time of publication, no known patch exists.
Vulnerability class: Buffer Overflow
EPSS: 0.005 (38.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H.
Affected products
- Riot-os Riot — versions <= 2025.10
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-25139?
- CVE-2026-25139 is a critical-severity vulnerability in Riot-Os Riot, classified under Out-of-bounds Read. CVSS score: 9.1/10. Published 2026-02-04.
- How severe is CVE-2026-25139?
- Critical severity. CVSS v3 base score is 9.1 out of 10.