# GSD-2021-1002325: NFSD: Fix exposure in nfsd4_decode_bitmap()

> An exposure in the Linux Kernel NFS server bitmap decoding allows potential information disclosure, requiring a kernel patch.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not stated
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 29 Nov 2021

## What is GSD-2021-1002325?

GSD-2021-1002325 is a vulnerability in Kernel, published on 29 Nov 2021. It can be exploited over the network, with no action from the victim.

### Official description

NFSD: Fix exposure in nfsd4_decode_bitmap()

This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven.
This ID is fixed in Linux Kernel version v5.15.5 by commit 10c22d9519f3f5939de61a1500aa3a926b778d3a, it was introduced in version v5.11 by commit d1c263a031e876ac3ca5223c728e4d98ed50b3c0. For more details please see the references link.

## Which versions are affected by GSD-2021-1002325?

1 open source package ship an affected version, including Kernel.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `Kernel` | Linux | All versions | None |

## How do I fix GSD-2021-1002325?

No fix has been published for GSD-2021-1002325 yet. Limit exposure of the affected software until one is available.

## Is GSD-2021-1002325 being exploited?

There is no known exploitation of GSD-2021-1002325 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GSD-2021-1002325 and fix it if it is affected.

What it is: GSD-2021-1002325 is a vulnerability in Kernel, published on 29 Nov 2021. It can be exploited over the network, with no action from the victim.
Exploitation: There is no known exploitation of GSD-2021-1002325 in the wild and no public exploit code.

Affected packages and fixed versions:
- Kernel (Linux): affected all versions; no fix listed

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/GSD-2021-1002325/ (Markdown: https://insights.sbomify.com/GSD-2021-1002325/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GSD-2021-1002325

---
From sbomify Insights: https://insights.sbomify.com/GSD-2021-1002325/
Summaries are generated and may contain mistakes; the official description above is the record.