# CVE-2026-64565: Input: ims-pcu - fix heap-buffer-overflow in ims_pcu_process_data()

> A heap buffer overflow in the Linux kernel ims-pcu driver allows local attackers with physical access to execute arbitrary code via a malicious USB device.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 4 Aug 2026
- **Updated:** 19 Aug 2026
- **Also known as:** AZL-94401, BELL-CVE-2026-64565, DEBIAN-CVE-2026-64565, GHSA-36cq-f2m4-833w, UBUNTU-CVE-2026-64565

## What is CVE-2026-64565?

CVE-2026-64565 is a memory corruption vulnerability in Linux, published on 4 Aug 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

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

Input: ims-pcu - fix heap-buffer-overflow in ims_pcu_process_data()

The `ims_pcu_process_data()` processes incoming URB data byte by byte.
However, it fails to check if the `read_pos` index exceeds
IMS_PCU_BUF_SIZE.

If a malicious USB device sends a packet larger than IMS_PCU_BUF_SIZE,
`read_pos` will increment indefinitely. Moreover, since `read_pos` is
located immediately after `read_buf`, the attacker can overwrite
`read_pos` itself to arbitrarily control the index.

This manipulated `read_pos` is subsequently used in
`ims_pcu_handle_response()` to copy data into `cmd_buf`, leading to a
heap buffer overflow.

Specifically, an attacker can overwrite the `cmd_done.wait.head` located
at offset 136 relative to `cmd_buf` in the `ims_pcu_handle_response()`.
Consequently, when the driver calls `complete(&pcu->cmd_done)`, it
triggers a control flow hijack by using the manipulated pointer.

Fix this by adding a bounds check for `read_pos` before writing to
`read_buf`. If the packet is too long, discard it, log a warning,
and reset the parser state.

[dtor: factor out resetting packet state, reset checksum as well]

## Which versions are affected by CVE-2026-64565?


## How do I fix CVE-2026-64565?

Apply the vendor's patch.

## Is CVE-2026-64565 being exploited?

There is no known exploitation of CVE-2026-64565 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-64565 and fix it if it is affected.

What it is: CVE-2026-64565 is a memory corruption vulnerability in Linux, published on 4 Aug 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-64565 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-2026-64565/ (Markdown: https://insights.sbomify.com/CVE-2026-64565/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64565
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64565
- OSV: https://osv.dev/vulnerability/CVE-2026-64565

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64565/
Summaries are generated and may contain mistakes; the official description above is the record.