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

> An attacker can cause memory corruption and crashes in RIOT OS by sending crafted serial or TCP data to the ethos utility due to missing bounds checks.

- **Severity:** Medium 6.8 (`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`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 12 Jan 2026
- **Updated:** 14 Jul 2026
- **Also known as:** GHSA-rfq2-gv2r-vgjg

## What is CVE-2026-22214?

CVE-2026-22214 is a medium-severity memory corruption vulnerability in RIOT OS, published on 12 Jan 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### 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.

Weakness: CWE-121 (Stack-based Buffer Overflow)

## Which versions are affected by CVE-2026-22214?

It affects 1 product.


Products: Riot-Os Riot.

## How do I fix CVE-2026-22214?

No fix has been published for CVE-2026-22214 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-22214 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-22214 exists.

## Other vulnerabilities in RIOT OS

- [CVE-2024-32017](https://insights.sbomify.com/CVE-2024-32017/): Buffer overflows in RIOT (critical 9.8)
- [CVE-2023-33975](https://insights.sbomify.com/CVE-2023-33975/): RIOT-OS vulnerable to Out of Bounds Write in _rbuf_add (critical 9.8)
- [CVE-2023-24819](https://insights.sbomify.com/CVE-2023-24819/): RIOT-OS vulnerable to Buffer Overflow during IPHC receive (critical 9.8)
- [CVE-2023-24823](https://insights.sbomify.com/CVE-2023-24823/): RIOT-OS vulnerable to Packet Type Confusion during IPHC send (critical 9.8)
- [CVE-2021-27357](https://insights.sbomify.com/CVE-2021-27357/): Memory corruption in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-22214 and fix it if it is affected.

What it is: CVE-2026-22214 is a medium-severity memory corruption vulnerability in RIOT OS, published on 12 Jan 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-22214 exists.

Affected product: RIOT OS. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-22214/ (Markdown: https://insights.sbomify.com/CVE-2026-22214/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-22214
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-22214
- OSV: https://osv.dev/vulnerability/CVE-2026-22214

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-22214/
Summaries are generated and may contain mistakes; the official description above is the record.