# CVE-2026-74458: can: kvaser_usb_leaf: kvaser_usb_leaf_wait_cmd(): validate received command extents

> A flaw in the Linux kernel Kvaser USB CAN driver allows memory corruption via malformed USB commands, potentially leading to code execution or system crash.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 15 Aug 2026
- **Updated:** 19 Aug 2026
- **Also known as:** AZL-96111, BELL-CVE-2026-74458, DEBIAN-CVE-2026-74458, GHSA-2x39-h24h-r965, UBUNTU-CVE-2026-74458

## What is CVE-2026-74458?

CVE-2026-74458 is a memory corruption vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

can: kvaser_usb_leaf: kvaser_usb_leaf_wait_cmd(): validate received command extents

The wait and bulk receive paths walk variable-length commands from a
USB buffer. A nonzero command shorter than CMD_HEADER_LEN can still be
dispatched, and the wait path copies a matching command into a fixed
caller-owned struct kvaser_cmd using the device-provided length.

Reject nonzero commands that do not contain the fixed header or that
extend beyond the current USB buffer item. In the wait path, also reject
a matching command that exceeds the destination before copying it.

## Which versions are affected by CVE-2026-74458?


## How do I fix CVE-2026-74458?

Apply the vendor's patch.

## Is CVE-2026-74458 being exploited?

There is no known exploitation of CVE-2026-74458 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74458 and fix it if it is affected.

What it is: CVE-2026-74458 is a memory corruption vulnerability in Linux, published on 15 Aug 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-2026-74458 in the wild and no public exploit code.

Affected product: Linux. 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-2026-74458/ (Markdown: https://insights.sbomify.com/CVE-2026-74458/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74458
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74458
- OSV: https://osv.dev/vulnerability/CVE-2026-74458

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74458/
Summaries are generated and may contain mistakes; the official description above is the record.