# CVE-2023-52752: smb: client: fix use-after-free bug in cifs_debug_data_proc_show()

> A use-after-free bug in the Linux kernel CIFS client allows a local attacker to cause a system crash by reading debug data during session teardown.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:** 21 May 2024
- **Updated:** 5 Aug 2026
- **Also known as:** AZL-42208, BELL-CVE-2023-52752, DEBIAN-CVE-2023-52752, GHSA-c3wm-p2jr-8f5g, SUSE-SU-2024:3764-1, SUSE-SU-2024:3775-1, SUSE-SU-2024:3885-1, UBUNTU-CVE-2023-52752

## What is CVE-2023-52752?

CVE-2023-52752 is a high-severity use after free vulnerability in Debian Debian Linux, published on 21 May 2024. 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:

smb: client: fix use-after-free bug in cifs_debug_data_proc_show()

Skip SMB sessions that are being teared down
(e.g. @ses->ses_status == SES_EXITING) in cifs_debug_data_proc_show()
to avoid use-after-free in @ses.

This fixes the following GPF when reading from /proc/fs/cifs/DebugData
while mounting and umounting

  [ 816.251274] general protection fault, probably for non-canonical
  address 0x6b6b6b6b6b6b6d81: 0000 [#1] PREEMPT SMP NOPTI
  ...
  [  816.260138] Call Trace:
  [  816.260329]  <TASK>
  [  816.260499]  ? die_addr+0x36/0x90
  [  816.260762]  ? exc_general_protection+0x1b3/0x410
  [  816.261126]  ? asm_exc_general_protection+0x26/0x30
  [  816.261502]  ? cifs_debug_tcon+0xbd/0x240 [cifs]
  [  816.261878]  ? cifs_debug_tcon+0xab/0x240 [cifs]
  [  816.262249]  cifs_debug_data_proc_show+0x516/0xdb0 [cifs]
  [  816.262689]  ? seq_read_iter+0x379/0x470
  [  816.262995]  seq_read_iter+0x118/0x470
  [  816.263291]  proc_reg_read_iter+0x53/0x90
  [  816.263596]  ? srso_alias_return_thunk+0x5/0x7f
  [  816.263945]  vfs_read+0x201/0x350
  [  816.264211]  ksys_read+0x75/0x100
  [  816.264472]  do_syscall_64+0x3f/0x90
  [  816.264750]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
  [  816.265135] RIP: 0033:0x7fd5e669d381

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2023-52752?

It affects 2 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `kernel-livepatch-SLE15-SP6-RT_Update_2` | SUSE:Linux Enterprise Live Patching 15 SP6 | All versions | 2-150600.1.6.1 |
| `kernel-livepatch-SLE15-SP6-RT_Update_3` | SUSE:Linux Enterprise Live Patching 15 SP6 | All versions | 2-150600.2.1 |
| `kernel-livepatch-SLE15-SP6_Update_4` | SUSE:Linux Enterprise Live Patching 15 SP6 | All versions | 2-150600.13.6.1 |

Products: Debian Debian Linux, Linux kernel.

## How do I fix CVE-2023-52752?

Apply the vendor's patch.

## Is CVE-2023-52752 being exploited?

There is no known exploitation of CVE-2023-52752 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [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-2023-52752 and fix it if it is affected.

What it is: CVE-2023-52752 is a high-severity use after free vulnerability in Debian Debian Linux, published on 21 May 2024. 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-2023-52752 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-2023-52752/ (Markdown: https://insights.sbomify.com/CVE-2023-52752/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-52752
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-52752
- OSV: https://osv.dev/vulnerability/CVE-2023-52752

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-52752/
Summaries are generated and may contain mistakes; the official description above is the record.