# CVE-2024-53066: nfs: Fix KMSAN warning in decode_getfattr_attrs()

> An uninitialized pointer in the Linux kernel NFS client can cause a crash when processing file attributes, leading to denial of service.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Nov 2024
- **Updated:** 5 Aug 2026
- **Also known as:** AZL-53909, AZL-53915, BELL-CVE-2024-53066, DEBIAN-CVE-2024-53066, GHSA-fc6c-wh46-2q9r, UBUNTU-CVE-2024-53066

## What is CVE-2024-53066?

CVE-2024-53066 is a critical vulnerability in Linux kernel, published on 19 Nov 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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

nfs: Fix KMSAN warning in decode_getfattr_attrs()

Fix the following KMSAN warning:

CPU: 1 UID: 0 PID: 7651 Comm: cp Tainted: G    B
Tainted: [B]=BAD_PAGE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009)
=====================================================
=====================================================
BUG: KMSAN: uninit-value in decode_getfattr_attrs+0x2d6d/0x2f90
 decode_getfattr_attrs+0x2d6d/0x2f90
 decode_getfattr_generic+0x806/0xb00
 nfs4_xdr_dec_getattr+0x1de/0x240
 rpcauth_unwrap_resp_decode+0xab/0x100
 rpcauth_unwrap_resp+0x95/0xc0
 call_decode+0x4ff/0xb50
 __rpc_execute+0x57b/0x19d0
 rpc_execute+0x368/0x5e0
 rpc_run_task+0xcfe/0xee0
 nfs4_proc_getattr+0x5b5/0x990
 __nfs_revalidate_inode+0x477/0xd00
 nfs_access_get_cached+0x1021/0x1cc0
 nfs_do_access+0x9f/0xae0
 nfs_permission+0x1e4/0x8c0
 inode_permission+0x356/0x6c0
 link_path_walk+0x958/0x1330
 path_lookupat+0xce/0x6b0
 filename_lookup+0x23e/0x770
 vfs_statx+0xe7/0x970
 vfs_fstatat+0x1f2/0x2c0
 __se_sys_newfstatat+0x67/0x880
 __x64_sys_newfstatat+0xbd/0x120
 x64_sys_call+0x1826/0x3cf0
 do_syscall_64+0xd0/0x1b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The KMSAN warning is triggered in decode_getfattr_attrs(), when calling
decode_attr_mdsthreshold(). It appears that fattr->mdsthreshold is not
initialized.

Fix the issue by initializing fattr->mdsthreshold to NULL in
nfs_fattr_init().

Weakness: CWE-908 (Use of Uninitialized Resource)

## Which versions are affected by CVE-2024-53066?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-53066?

Apply the vendor's patch.

## Is CVE-2024-53066 being exploited?

There is no known exploitation of CVE-2024-53066 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-2024-53066 and fix it if it is affected.

What it is: CVE-2024-53066 is a critical vulnerability in Linux kernel, published on 19 Nov 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-53066 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-2024-53066/ (Markdown: https://insights.sbomify.com/CVE-2024-53066/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-53066
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-53066
- OSV: https://osv.dev/vulnerability/CVE-2024-53066

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-53066/
Summaries are generated and may contain mistakes; the official description above is the record.