# CVE-2025-38400: nfs: Clean up /proc/net/rpc/nfs when nfs_fs_proc_net_init() fails.

> A failure in NFS initialization leaves /proc entries uncleaned, causing kernel warnings and potential resource leaks during namespace operations.

- **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:** 25 Jul 2025
- **Updated:** 15 Oct 2026
- **Also known as:** AZL-73019, BELL-CVE-2025-38400, DEBIAN-CVE-2025-38400, GHSA-ch6p-gm8m-r8fm, ROOT-OS-DEBIAN-11-CVE-2025-38400, ROOT-OS-UBUNTU-2204-CVE-2025-38400, ROOT-OS-UBUNTU-2404-CVE-2025-38400, UBUNTU-CVE-2025-38400

## What is CVE-2025-38400?

CVE-2025-38400 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 25 Jul 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:

nfs: Clean up /proc/net/rpc/nfs when nfs_fs_proc_net_init() fails.

syzbot reported a warning below [1] following a fault injection in
nfs_fs_proc_net_init(). [0]

When nfs_fs_proc_net_init() fails, /proc/net/rpc/nfs is not removed.

Later, rpc_proc_exit() tries to remove /proc/net/rpc, and the warning
is logged as the directory is not empty.

Let's handle the error of nfs_fs_proc_net_init() properly.

[0]:
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 1 UID: 0 PID: 6120 Comm: syz.2.27 Not tainted 6.16.0-rc1-syzkaller-00010-g2c4a1f3fe03e #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
  dump_stack_lvl (lib/dump_stack.c:123)
 should_fail_ex (lib/fault-inject.c:73 lib/fault-inject.c:174)
 should_failslab (mm/failslab.c:46)
 kmem_cache_alloc_noprof (mm/slub.c:4178 mm/slub.c:4204)
 __proc_create (fs/proc/generic.c:427)
 proc_create_reg (fs/proc/generic.c:554)
 proc_create_net_data (fs/proc/proc_net.c:120)
 nfs_fs_proc_net_init (fs/nfs/client.c:1409)
 nfs_net_init (fs/nfs/inode.c:2600)
 ops_init (net/core/net_namespace.c:138)
 setup_net (net/core/net_namespace.c:443)
 copy_net_ns (net/core/net_namespace.c:576)
 create_new_namespaces (kernel/nsproxy.c:110)
 unshare_nsproxy_namespaces (kernel/nsproxy.c:218 (discriminator 4))
 ksys_unshare (kernel/fork.c:3123)
 __x64_sys_unshare (kernel/fork.c:3190)
 do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
 entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
 </TASK>

[1]:
remove_proc_entry: removing non-empty directory 'net/rpc', leaking at least 'nfs'
 WARNING: CPU: 1 PID: 6120 at fs/proc/generic.c:727 remove_proc_entry+0x45e/0x530 fs/proc/generic.c:727
Modules linked in:
CPU: 1 UID: 0 PID: 6120 Comm: syz.2.27 Not tainted 6.16.0-rc1-syzkaller-00010-g2c4a1f3fe03e #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
 RIP: 0010:remove_proc_entry+0x45e/0x530 fs/proc/generic.c:727
Code: 3c 02 00 0f 85 85 00 00 00 48 8b 93 d8 00 00 00 4d 89 f0 4c 89 e9 48 c7 c6 40 ba a2 8b 48 c7 c7 60 b9 a2 8b e8 33 81 1d ff 90 <0f> 0b 90 90 e9 5f fe ff ff e8 04 69 5e ff 90 48 b8 00 00 00 00 00
RSP: 0018:ffffc90003637b08 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff88805f534140 RCX: ffffffff817a92c8
RDX: ffff88807da99e00 RSI: ffffffff817a92d5 RDI: 0000000000000001
RBP: ffff888033431ac0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffff888033431a00
R13: ffff888033431ae4 R14: ffff888033184724 R15: dffffc0000000000
FS:  0000555580328500(0000) GS:ffff888124a62000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f71733743e0 CR3: 000000007f618000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
  sunrpc_exit_net+0x46/0x90 net/sunrpc/sunrpc_syms.c:76
  ops_exit_list net/core/net_namespace.c:200 [inline]
  ops_undo_list+0x2eb/0xab0 net/core/net_namespace.c:253
  setup_net+0x2e1/0x510 net/core/net_namespace.c:457
  copy_net_ns+0x2a6/0x5f0 net/core/net_namespace.c:574
  create_new_namespaces+0x3ea/0xa90 kernel/nsproxy.c:110
  unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:218
  ksys_unshare+0x45b/0xa40 kernel/fork.c:3121
  __do_sys_unshare kernel/fork.c:3192 [inline]
  __se_sys_unshare kernel/fork.c:3190 [inline]
  __x64_sys_unshare+0x31/0x40 kernel/fork.c:3190
  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
  do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa1a6b8e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c
---truncated---

## Which versions are affected by CVE-2025-38400?

It affects 2 products.


Products: Debian Debian Linux, Linux kernel.

## How do I fix CVE-2025-38400?

Apply the vendor's patch.

## Is CVE-2025-38400 being exploited?

There is no known exploitation of CVE-2025-38400 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

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- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-38400 and fix it if it is affected.

What it is: CVE-2025-38400 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 25 Jul 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-2025-38400 in the wild and no public exploit code.

Affected product: Debian Debian 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-2025-38400/ (Markdown: https://insights.sbomify.com/CVE-2025-38400/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-38400
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-38400
- OSV: https://osv.dev/vulnerability/CVE-2025-38400

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-38400/
Summaries are generated and may contain mistakes; the official description above is the record.