# CVE-2026-74459: can: etas_es58x: es58x_read_bulk_callback(): fix RX buffer leak on URB resubmit failure

> A memory leak in the Linux kernel CAN driver allows attackers to cause denial of service by triggering URB resubmit failures.

- **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:** BELL-CVE-2026-74459, DEBIAN-CVE-2026-74459, GHSA-5m9p-vm8m-7vmc, UBUNTU-CVE-2026-74459

## What is CVE-2026-74459?

CVE-2026-74459 is a denial of service 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: etas_es58x: es58x_read_bulk_callback(): fix RX buffer leak on URB resubmit failure

es58x_read_bulk_callback() resubmits the RX URB after processing a received
packet. If the resubmit succeeds, the URB remains anchored and will be
handled by the normal RX path or by teardown.

However, if usb_submit_urb() fails, the callback unanchors the URB and then
returns directly. This skips the existing free_urb path, so the coherent
transfer buffer allocated with usb_alloc_coherent() is not released.

Reuse the existing free_urb path after a resubmit failure so that the RX
coherent buffer is freed before leaving the callback.

## Which versions are affected by CVE-2026-74459?


## How do I fix CVE-2026-74459?

Apply the vendor's patch.

## Is CVE-2026-74459 being exploited?

There is no known exploitation of CVE-2026-74459 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74459 and fix it if it is affected.

What it is: CVE-2026-74459 is a denial of service 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-2026-74459 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-2026-74459/ (Markdown: https://insights.sbomify.com/CVE-2026-74459/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74459
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74459
- OSV: https://osv.dev/vulnerability/CVE-2026-74459

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74459/
Summaries are generated and may contain mistakes; the official description above is the record.