# CVE-2026-53147: thunderbolt: Validate XDomain request packet size before type cast

> A malicious Thunderbolt peer can trigger out-of-bounds reads in the Linux kernel by sending undersized XDomain packets, potentially causing information disclosure or crashes.

- **Severity:** High 8.1 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H`)
- **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:** 25 Jun 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-90585, BELL-CVE-2026-53147, DEBIAN-CVE-2026-53147, GHSA-vrfr-cw9w-gwrx, ROOT-OS-DEBIAN-11-CVE-2026-53147, ROOT-OS-DEBIAN-12-CVE-2026-53147, ROOT-OS-UBUNTU-2204-CVE-2026-53147, ROOT-OS-UBUNTU-2404-CVE-2026-53147, UBUNTU-CVE-2026-53147

## What is CVE-2026-53147?

CVE-2026-53147 is a high-severity memory corruption vulnerability in Linux kernel, published on 25 Jun 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:

thunderbolt: Validate XDomain request packet size before type cast

tb_xdp_handle_request() casts the received packet buffer to
protocol-specific structs without verifying that the allocation
is large enough for the target type.  A peer can send a minimal
XDomain packet that passes the generic header length check but is
shorter than the struct accessed after the cast, causing out-of-
bounds reads from the kmemdup allocation.

Plumb the packet length through xdomain_request_work and validate
it against the expected struct size before each cast.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-53147?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-53147?

Apply the vendor's patch.

## Is CVE-2026-53147 being exploited?

There is no known exploitation of CVE-2026-53147 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-2026-53147 and fix it if it is affected.

What it is: CVE-2026-53147 is a high-severity memory corruption vulnerability in Linux kernel, published on 25 Jun 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-2026-53147 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-2026-53147/ (Markdown: https://insights.sbomify.com/CVE-2026-53147/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53147
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53147
- OSV: https://osv.dev/vulnerability/CVE-2026-53147

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53147/
Summaries are generated and may contain mistakes; the official description above is the record.