# CVE-2026-5071: can: Local Denial of Service via SocketCAN Send

> A local attacker can cause a denial of service or leak memory by sending truncated SocketCAN frames in production builds where assertions are disabled.

- **Severity:** Medium 6.1 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 30 May 2026
- **Updated:** 15 Oct 2026
- **Also known as:** GHSA-c3w6-x7m3-3c58

## What is CVE-2026-5071?

CVE-2026-5071 is a medium-severity denial of service vulnerability in Zephyrproject Zephyr, published on 30 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

The SocketCAN implementation validates the length of a user-provided buffer containing a socketcan_frame object using only a NET_ASSERT statement in zcan_sendto_ctx() before dereferencing it in socketcan_to_can_frame(). In production builds where assertions are disabled, a userspace application that controls the length passed to a sendto syscall can supply an incomplete or truncated frame, causing socketcan_to_can_frame() to dereference fields beyond the end of the buffer. This results in an out-of-bounds read that can cause denial-of-service crashes or, because the parsed frame contents are transmitted on the network, leak adjacent memory.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-5071?

It affects 1 product.


Products: Zephyrproject Zephyr.

## How do I fix CVE-2026-5071?

No fix has been published for CVE-2026-5071 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-5071 being exploited?

There is no known exploitation of CVE-2026-5071 in the wild and no public exploit code.

## Other vulnerabilities in Zephyrproject Zephyr

- [CVE-2026-5067](https://insights.sbomify.com/CVE-2026-5067/): Out-of-bounds read/write in HTTP WebSocket upgrade via non-null-terminated Sec-WebSocket-Key (critical 9.8)
- [CVE-2022-3806](https://insights.sbomify.com/CVE-2022-3806/): Bluetooth HCI Error Handling Double Free (critical 9.8)
- [CVE-2017-14199](https://insights.sbomify.com/CVE-2017-14199/): Memory corruption in getaddrinfo (critical 9.8)
- [CVE-2018-1000800](https://insights.sbomify.com/CVE-2018-1000800/): Null dereference in n/a (critical 9.8)
- [CVE-2021-3329](https://insights.sbomify.com/CVE-2021-3329/): DOS: Incorrect handling of the initial HCI ACL_MTU handshake packet leads to crash of bluetooth host layer (critical 9.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-5071 and fix it if it is affected.

What it is: CVE-2026-5071 is a medium-severity denial of service vulnerability in Zephyrproject Zephyr, published on 30 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-5071 in the wild and no public exploit code.

Affected product: Zephyrproject Zephyr. 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-2026-5071/ (Markdown: https://insights.sbomify.com/CVE-2026-5071/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-5071
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-5071
- OSV: https://osv.dev/vulnerability/CVE-2026-5071

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-5071/
Summaries are generated and may contain mistakes; the official description above is the record.