# CVE-2026-64101: fwctl: pds: Validate RPC input size before parsing

> A missing size check in the Linux kernel pds driver allows out-of-bounds reads, potentially causing a denial of service.

- **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:** 19 Jul 2026
- **Updated:** 19 Jul 2026
- **Also known as:** BELL-CVE-2026-64101, DEBIAN-CVE-2026-64101, GHSA-954m-592c-4vpc, UBUNTU-CVE-2026-64101

## What is CVE-2026-64101?

CVE-2026-64101 is a medium-severity vulnerability in Linux kernel, published on 19 Jul 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:

fwctl: pds: Validate RPC input size before parsing

The fwctl core allocates the device-specific RPC input buffer with
fwctl_rpc.in_len and passes that buffer to the driver callback.

pdsfc_fw_rpc() casts the buffer to struct fwctl_rpc_pds and then calls
pdsfc_validate_rpc(), which reads fields from that structure before
checking that the input buffer is large enough to contain it. A short
in_len can make pds_fwctl read beyond the allocation.

Reject pds RPC buffers that are smaller than struct fwctl_rpc_pds before
parsing any pds-specific fields.

## Which versions are affected by CVE-2026-64101?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-64101?

Apply the vendor's patch.

## Is CVE-2026-64101 being exploited?

There is no known exploitation of CVE-2026-64101 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-2026-64101 and fix it if it is affected.

What it is: CVE-2026-64101 is a medium-severity vulnerability in Linux kernel, published on 19 Jul 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-2026-64101 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-2026-64101/ (Markdown: https://insights.sbomify.com/CVE-2026-64101/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64101
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64101
- OSV: https://osv.dev/vulnerability/CVE-2026-64101

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64101/
Summaries are generated and may contain mistakes; the official description above is the record.