# CVE-2026-64519: NFSD: Fix infinite loop in layout state revocation

> An attacker can cause a denial of service in the Linux kernel's NFSD by triggering an infinite loop during layout state revocation.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Jul 2026
- **Updated:** 25 Jul 2026
- **Also known as:** BELL-CVE-2026-64519, DEBIAN-CVE-2026-64519, GHSA-gv69-m9qg-32px, ROOT-OS-UBUNTU-2204-CVE-2026-64519, UBUNTU-CVE-2026-64519

## What is CVE-2026-64519?

CVE-2026-64519 is a denial of service vulnerability in Linux, published on 25 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

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

NFSD: Fix infinite loop in layout state revocation

find_one_sb_stid() skips stids whose sc_status is non-zero, but the
SC_TYPE_LAYOUT case in nfsd4_revoke_states() never sets sc_status
before calling nfsd4_close_layout(). The retry loop therefore finds
the same layout stid on every iteration, hanging the revoker
indefinitely.

## Which versions are affected by CVE-2026-64519?


## How do I fix CVE-2026-64519?

Apply the vendor's patch.

## Is CVE-2026-64519 being exploited?

There is no known exploitation of CVE-2026-64519 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-64519 and fix it if it is affected.

What it is: CVE-2026-64519 is a denial of service vulnerability in Linux, published on 25 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-64519 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-2026-64519/ (Markdown: https://insights.sbomify.com/CVE-2026-64519/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64519
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64519
- OSV: https://osv.dev/vulnerability/CVE-2026-64519

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64519/
Summaries are generated and may contain mistakes; the official description above is the record.