Vulnerability · Published Jan 12, 2026 · Assigned by VulnCheck

CVE-2026-22214RIOT OS <= 2026.01-devel-317 Stack-Based Buffer Overflow in ethos Serial Frame Parser

Medium 6.8

In plain English

A medium-severity stack buffer overflow in RIOT OS from RIOT. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 40% of all known vulnerabilities).

Severity (CVSS 4.0)6.8Medium

Exploit odds (30 days)0.5%top 59.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

RIOT OS versions up to and including 2026.01-devel-317 contain a stack-based buffer overflow vulnerability in the ethos utility due to missing bounds checking when processing incoming serial frame data. The vulnerability occurs in the _handle_char() function, where incoming frame bytes are appended to a fixed-size stack buffer without verifying that the current write index remains within bounds. An attacker capable of sending crafted serial or TCP-framed input can cause the current write index to exceed the buffer size, resulting in a write past the end of the stack buffer. This condition leads to memory corruption and application crash.

Affected products (as reported)

Vendor	Product	Versions
RIOT	RIOT OS	0 – through 2026.01-devel-317

Weakness: CWE-121 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

References

https://seclists.org/fulldisclosure/2026/Jan/16 technical-description, exploit
https://www.riot-os.org/ product
https://github.com/RIOT-OS/RIOT product
https://www.vulncheck.com/advisories/riot-os-stack-based-buffer-overflow-in-ethos-serial-frame-parser third-party-advisory