# CVE-2026-46151: usb: usblp: fix heap leak in IEEE 1284 device ID via short response

> A malicious USB printer can leak uninitialized kernel heap memory to local users via the usblp driver's device ID handling.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/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:** Yes
- **Published:** 28 May 2026
- **Updated:** 15 Oct 2026
- **Also known as:** AZL-88941, BELL-CVE-2026-46151, DEBIAN-CVE-2026-46151, GHSA-589q-vfc2-j9cg, ROOT-OS-DEBIAN-11-CVE-2026-46151, ROOT-OS-DEBIAN-12-CVE-2026-46151, ROOT-OS-UBUNTU-2204-CVE-2026-46151, ROOT-OS-UBUNTU-2404-CVE-2026-46151, UBUNTU-CVE-2026-46151

## What is CVE-2026-46151?

CVE-2026-46151 is a medium-severity vulnerability in Linux kernel, published on 28 May 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:

usb: usblp: fix heap leak in IEEE 1284 device ID via short response

usblp_ctrl_msg() collapses the usb_control_msg() return value to
0/-errno, discarding the actual number of bytes transferred.  A broken
printer can complete the GET_DEVICE_ID control transfer short and the
driver has no way to know.

usblp_cache_device_id_string() reads the 2-byte big-endian length prefix
from the response and trusts it (clamped only to the buffer bounds).
The buffer is kmalloc(1024) at probe time. A device that sends exactly
two bytes (e.g. 0x03 0xFF, claiming a 1023-byte ID) leaves
device_id_string[2..1022] holding stale kmalloc heap.

That stale data is then exposed:
  - via the ieee1284_id sysfs attribute (sprintf("%s", buf+2), truncated
    at the first NUL in the stale heap), and
  - via the IOCNR_GET_DEVICE_ID ioctl, which copy_to_user()s the full
    claimed length regardless of NULs, up to 1021 bytes of uninitialized
    heap, with the leak size chosen by the device.

Fix this up by just zapping the buffer with zeros before each request
sent to the device.

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime)

## Which versions are affected by CVE-2026-46151?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-46151?

Apply the vendor's patch.

## Is CVE-2026-46151 being exploited?

There is no known exploitation of CVE-2026-46151 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-46151 and fix it if it is affected.

What it is: CVE-2026-46151 is a medium-severity vulnerability in Linux kernel, published on 28 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-2026-46151 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2026-46151/ (Markdown: https://insights.sbomify.com/CVE-2026-46151/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-46151
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-46151
- OSV: https://osv.dev/vulnerability/CVE-2026-46151

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-46151/
Summaries are generated and may contain mistakes; the official description above is the record.