# CVE-2025-22002: netfs: Call `invalidate_cache` only if implemented

> A null pointer dereference in the Linux kernel netfs subsystem causes a crash when cache writes fail on filesystems lacking invalidate_cache implementation.

- **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:** 3 Apr 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2025-22002, DEBIAN-CVE-2025-22002, GHSA-68gg-f4cj-w6g2, ROOT-OS-UBUNTU-2404-CVE-2025-22002, UBUNTU-CVE-2025-22002

## What is CVE-2025-22002?

CVE-2025-22002 is a medium-severity vulnerability in Linux kernel, published on 3 Apr 2025. 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:

netfs: Call `invalidate_cache` only if implemented

Many filesystems such as NFS and Ceph do not implement the
`invalidate_cache` method.  On those filesystems, if writing to the
cache (`NETFS_WRITE_TO_CACHE`) fails for some reason, the kernel
crashes like this:

 BUG: kernel NULL pointer dereference, address: 0000000000000000
 #PF: supervisor instruction fetch in kernel mode
 #PF: error_code(0x0010) - not-present page
 PGD 0 P4D 0
 Oops: Oops: 0010 [#1] SMP PTI
 CPU: 9 UID: 0 PID: 3380 Comm: kworker/u193:11 Not tainted 6.13.3-cm4all1-hp #437
 Hardware name: HP ProLiant DL380 Gen9/ProLiant DL380 Gen9, BIOS P89 10/17/2018
 Workqueue: events_unbound netfs_write_collection_worker
 RIP: 0010:0x0
 Code: Unable to access opcode bytes at 0xffffffffffffffd6.
 RSP: 0018:ffff9b86e2ca7dc0 EFLAGS: 00010202
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 7fffffffffffffff
 RDX: 0000000000000001 RSI: ffff89259d576a18 RDI: ffff89259d576900
 RBP: ffff89259d5769b0 R08: ffff9b86e2ca7d28 R09: 0000000000000002
 R10: ffff89258ceaca80 R11: 0000000000000001 R12: 0000000000000020
 R13: ffff893d158b9338 R14: ffff89259d576900 R15: ffff89259d5769b0
 FS:  0000000000000000(0000) GS:ffff893c9fa40000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: ffffffffffffffd6 CR3: 000000054442e003 CR4: 00000000001706f0
 Call Trace:
  <TASK>
  ? __die+0x1f/0x60
  ? page_fault_oops+0x15c/0x460
  ? try_to_wake_up+0x2d2/0x530
  ? exc_page_fault+0x5e/0x100
  ? asm_exc_page_fault+0x22/0x30
  netfs_write_collection_worker+0xe9f/0x12b0
  ? xs_poll_check_readable+0x3f/0x80
  ? xs_stream_data_receive_workfn+0x8d/0x110
  process_one_work+0x134/0x2d0
  worker_thread+0x299/0x3a0
  ? __pfx_worker_thread+0x10/0x10
  kthread+0xba/0xe0
  ? __pfx_kthread+0x10/0x10
  ret_from_fork+0x30/0x50
  ? __pfx_kthread+0x10/0x10
  ret_from_fork_asm+0x1a/0x30
  </TASK>
 Modules linked in:
 CR2: 0000000000000000

This patch adds the missing `NULL` check.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2025-22002?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-22002?

Apply the vendor's patch.

## Is CVE-2025-22002 being exploited?

There is no known exploitation of CVE-2025-22002 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-2025-22002 and fix it if it is affected.

What it is: CVE-2025-22002 is a medium-severity vulnerability in Linux kernel, published on 3 Apr 2025. 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-2025-22002 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-2025-22002/ (Markdown: https://insights.sbomify.com/CVE-2025-22002/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-22002
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-22002
- OSV: https://osv.dev/vulnerability/CVE-2025-22002

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-22002/
Summaries are generated and may contain mistakes; the official description above is the record.