# CVE-2026-74457: can: peak_usb: add bounds check for USB channel index

> A missing bounds check in the Linux kernel peak_usb driver allows a local attacker with USB access to trigger a heap out-of-bounds read, causing a kernel panic.

- **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-96186, BELL-CVE-2026-74457, DEBIAN-CVE-2026-74457, GHSA-hc9g-h2c2-6wf9, UBUNTU-CVE-2026-74457

## What is CVE-2026-74457?

CVE-2026-74457 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: peak_usb: add bounds check for USB channel index

The channel control index ctrl_idx is derived from rx->len which comes
directly from a device USB payload. The mask 0x0f allows values 0-15, but
the array size of usb_if->dev[] is only 2. Values 2-15 cause heap
out-of-bounds read, eventually causing kernel panic in the IRQ context.

Add bounds checking for ctrl_idx before the array access in both
pcan_usb_pro_handle_canmsg() and pcan_usb_pro_handle_error().

## Which versions are affected by CVE-2026-74457?


## How do I fix CVE-2026-74457?

Apply the vendor's patch.

## Is CVE-2026-74457 being exploited?

There is no known exploitation of CVE-2026-74457 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74457 and fix it if it is affected.

What it is: CVE-2026-74457 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-2026-74457 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-2026-74457/ (Markdown: https://insights.sbomify.com/CVE-2026-74457/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74457
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74457
- OSV: https://osv.dev/vulnerability/CVE-2026-74457

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74457/
Summaries are generated and may contain mistakes; the official description above is the record.