# CVE-2024-27398: Bluetooth: Fix use-after-free bugs caused by sco_sock_timeout

> A use-after-free vulnerability in the Linux kernel Bluetooth subsystem allows attackers to execute arbitrary code or escalate privileges via crafted socket operations.

- **Severity:** High 8.0 (`CVSS:3.1/AV:A/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:** 13 May 2024
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2024-27398, DEBIAN-CVE-2024-27398, GHSA-45cm-4v3w-5jpw, UBUNTU-CVE-2024-27398

## What is CVE-2024-27398?

CVE-2024-27398 is a high-severity use after free vulnerability in Debian Debian Linux, published on 13 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:

Bluetooth: Fix use-after-free bugs caused by sco_sock_timeout

When the sco connection is established and then, the sco socket
is releasing, timeout_work will be scheduled to judge whether
the sco disconnection is timeout. The sock will be deallocated
later, but it is dereferenced again in sco_sock_timeout. As a
result, the use-after-free bugs will happen. The root cause is
shown below:

    Cleanup Thread               |      Worker Thread
sco_sock_release                 |
  sco_sock_close                 |
    __sco_sock_close             |
      sco_sock_set_timer         |
        schedule_delayed_work    |
  sco_sock_kill                  |    (wait a time)
    sock_put(sk) //FREE          |  sco_sock_timeout
                                 |    sock_hold(sk) //USE

The KASAN report triggered by POC is shown below:

[   95.890016] ==================================================================
[   95.890496] BUG: KASAN: slab-use-after-free in sco_sock_timeout+0x5e/0x1c0
[   95.890755] Write of size 4 at addr ffff88800c388080 by task kworker/0:0/7
...
[   95.890755] Workqueue: events sco_sock_timeout
[   95.890755] Call Trace:
[   95.890755]  <TASK>
[   95.890755]  dump_stack_lvl+0x45/0x110
[   95.890755]  print_address_description+0x78/0x390
[   95.890755]  print_report+0x11b/0x250
[   95.890755]  ? __virt_addr_valid+0xbe/0xf0
[   95.890755]  ? sco_sock_timeout+0x5e/0x1c0
[   95.890755]  kasan_report+0x139/0x170
[   95.890755]  ? update_load_avg+0xe5/0x9f0
[   95.890755]  ? sco_sock_timeout+0x5e/0x1c0
[   95.890755]  kasan_check_range+0x2c3/0x2e0
[   95.890755]  sco_sock_timeout+0x5e/0x1c0
[   95.890755]  process_one_work+0x561/0xc50
[   95.890755]  worker_thread+0xab2/0x13c0
[   95.890755]  ? pr_cont_work+0x490/0x490
[   95.890755]  kthread+0x279/0x300
[   95.890755]  ? pr_cont_work+0x490/0x490
[   95.890755]  ? kthread_blkcg+0xa0/0xa0
[   95.890755]  ret_from_fork+0x34/0x60
[   95.890755]  ? kthread_blkcg+0xa0/0xa0
[   95.890755]  ret_from_fork_asm+0x11/0x20
[   95.890755]  </TASK>
[   95.890755]
[   95.890755] Allocated by task 506:
[   95.890755]  kasan_save_track+0x3f/0x70
[   95.890755]  __kasan_kmalloc+0x86/0x90
[   95.890755]  __kmalloc+0x17f/0x360
[   95.890755]  sk_prot_alloc+0xe1/0x1a0
[   95.890755]  sk_alloc+0x31/0x4e0
[   95.890755]  bt_sock_alloc+0x2b/0x2a0
[   95.890755]  sco_sock_create+0xad/0x320
[   95.890755]  bt_sock_create+0x145/0x320
[   95.890755]  __sock_create+0x2e1/0x650
[   95.890755]  __sys_socket+0xd0/0x280
[   95.890755]  __x64_sys_socket+0x75/0x80
[   95.890755]  do_syscall_64+0xc4/0x1b0
[   95.890755]  entry_SYSCALL_64_after_hwframe+0x67/0x6f
[   95.890755]
[   95.890755] Freed by task 506:
[   95.890755]  kasan_save_track+0x3f/0x70
[   95.890755]  kasan_save_free_info+0x40/0x50
[   95.890755]  poison_slab_object+0x118/0x180
[   95.890755]  __kasan_slab_free+0x12/0x30
[   95.890755]  kfree+0xb2/0x240
[   95.890755]  __sk_destruct+0x317/0x410
[   95.890755]  sco_sock_release+0x232/0x280
[   95.890755]  sock_close+0xb2/0x210
[   95.890755]  __fput+0x37f/0x770
[   95.890755]  task_work_run+0x1ae/0x210
[   95.890755]  get_signal+0xe17/0xf70
[   95.890755]  arch_do_signal_or_restart+0x3f/0x520
[   95.890755]  syscall_exit_to_user_mode+0x55/0x120
[   95.890755]  do_syscall_64+0xd1/0x1b0
[   95.890755]  entry_SYSCALL_64_after_hwframe+0x67/0x6f
[   95.890755]
[   95.890755] The buggy address belongs to the object at ffff88800c388000
[   95.890755]  which belongs to the cache kmalloc-1k of size 1024
[   95.890755] The buggy address is located 128 bytes inside of
[   95.890755]  freed 1024-byte region [ffff88800c388000, ffff88800c388400)
[   95.890755]
[   95.890755] The buggy address belongs to the physical page:
[   95.890755] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88800c38a800 pfn:0xc388
[   95.890755] head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
[   95.890755] ano
---truncated---

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2024-27398?

It affects 3 products.


Products: Debian Debian Linux, Fedoraproject Fedora, Linux kernel.

## How do I fix CVE-2024-27398?

Apply the vendor's patch.

## Is CVE-2024-27398 being exploited?

There is no known exploitation of CVE-2024-27398 in the wild and no public exploit code.

Public exploit code:

- CVE-2024-27398 POC (github_poc): https://github.com/secunnix/CVE-2024-27398

## 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-2024-27398 and fix it if it is affected.

What it is: CVE-2024-27398 is a high-severity use after free vulnerability in Debian Debian Linux, published on 13 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-2024-27398 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-2024-27398/ (Markdown: https://insights.sbomify.com/CVE-2024-27398/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-27398
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-27398
- OSV: https://osv.dev/vulnerability/CVE-2024-27398

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-27398/
Summaries are generated and may contain mistakes; the official description above is the record.
