# CVE-2026-53361: af_unix: Set gc_in_progress to true in unix_gc().

> A race condition in the Linux kernel's Unix socket garbage collection can lead to denial of service due to incorrect state handling.

- **Severity:** High 7.1 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/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:** 4 Jul 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-92004, BELL-CVE-2026-53361, DEBIAN-CVE-2026-53361, GHSA-h72j-p4f7-vrcj, ROOT-OS-DEBIAN-12-CVE-2026-53361, ROOT-OS-UBUNTU-2404-CVE-2026-53361, UBUNTU-CVE-2026-53361

## What is CVE-2026-53361?

CVE-2026-53361 is a high-severity vulnerability in Linux kernel, published on 4 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:

af_unix: Set gc_in_progress to true in unix_gc().

Igor Ushakov reported that unix_gc() could run with gc_in_progress
being false if the work is scheduled while running:

  Thread 1         Thread 2                     Thread 3
  --------         --------                     --------
                   unix_schedule_gc()           unix_schedule_gc()
                   `- if (!gc_in_progress)      `- if (!gc_in_progress)
                      |- gc_in_progress = true     |
                      `- queue_work()              |
  unix_gc() <----------------/                     |
  |                                                |- gc_in_progress = true
  ...                                              `- queue_work()
  |                                                       |
  `- gc_in_progress = false                               |
                                                          |
  unix_gc() <---------------------------------------------'
  |
  ... /* gc_in_progress == false */
  |
  `- gc_in_progress = false

unix_peek_fpl() relies on gc_in_progress not to confuse GC
by MSG_PEEK.

Let's set gc_in_progress to true in unix_gc().

Weakness: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2026-53361?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-53361?

Apply the vendor's patch.

## Is CVE-2026-53361 being exploited?

There is no known exploitation of CVE-2026-53361 in the wild and no public exploit code.

Public exploit code:

- CVE-2026-53361 AF_UNIX GC vs MSG_PEEK use-after-free container escape (github_poc): https://github.com/sgkdev/bad_garbage

## 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-2026-53361 and fix it if it is affected.

What it is: CVE-2026-53361 is a high-severity vulnerability in Linux kernel, published on 4 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-2026-53361 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-2026-53361/ (Markdown: https://insights.sbomify.com/CVE-2026-53361/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53361
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53361
- OSV: https://osv.dev/vulnerability/CVE-2026-53361

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53361/
Summaries are generated and may contain mistakes; the official description above is the record.