# CVE-2026-52930: ipc/shm: serialize orphan cleanup with shm_nattch updates

> A race condition in Linux kernel shared memory cleanup allows attackers to cause a denial of service by triggering inconsistent state during orphaned segment destruction.

- **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:** 24 Jun 2026
- **Updated:** 15 Oct 2026
- **Also known as:** AZL-90429, BELL-CVE-2026-52930, DEBIAN-CVE-2026-52930, GHSA-5g46-hmw3-w78x, ROOT-OS-DEBIAN-11-CVE-2026-52930, ROOT-OS-DEBIAN-12-CVE-2026-52930, ROOT-OS-UBUNTU-2204-CVE-2026-52930, ROOT-OS-UBUNTU-2404-CVE-2026-52930, UBUNTU-CVE-2026-52930

## What is CVE-2026-52930?

CVE-2026-52930 is a medium-severity vulnerability in Linux kernel, published on 24 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:

ipc/shm: serialize orphan cleanup with shm_nattch updates

shm_destroy_orphaned() walks the shm idr under shm_ids(ns).rwsem, but that
does not serialize all fields tested by shm_may_destroy().  In particular,
shm_nattch is updated while holding shm_perm.lock, and attach paths can do
that without holding the rwsem.

Do not decide that an orphaned segment is unused before taking the object
lock.  Move the shm_may_destroy() check under shm_perm.lock, matching the
other destroy paths, and unlock the segment when it no longer qualifies
for removal.

## Which versions are affected by CVE-2026-52930?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-52930?

Apply the vendor's patch.

## Is CVE-2026-52930 being exploited?

There is no known exploitation of CVE-2026-52930 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-2026-52930 and fix it if it is affected.

What it is: CVE-2026-52930 is a medium-severity vulnerability in Linux kernel, published on 24 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-2026-52930 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-2026-52930/ (Markdown: https://insights.sbomify.com/CVE-2026-52930/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-52930
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-52930
- OSV: https://osv.dev/vulnerability/CVE-2026-52930

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-52930/
Summaries are generated and may contain mistakes; the official description above is the record.