# CVE-2024-50255: Bluetooth: hci: fix null-ptr-deref in hci_read_supported_codecs

> A null pointer dereference in the Linux kernel Bluetooth subsystem allows local attackers to cause a system crash.

- **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:** 9 Nov 2024
- **Updated:** 11 May 2026
- **Also known as:** AZL-53298, BELL-CVE-2024-50255, DEBIAN-CVE-2024-50255, GHSA-5hxv-rgfg-978g, UBUNTU-CVE-2024-50255

## What is CVE-2024-50255?

CVE-2024-50255 is a medium-severity vulnerability in Linux kernel, published on 9 Nov 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: hci: fix null-ptr-deref in hci_read_supported_codecs

Fix __hci_cmd_sync_sk() to return not NULL for unknown opcodes.

__hci_cmd_sync_sk() returns NULL if a command returns a status event.
However, it also returns NULL where an opcode doesn't exist in the
hci_cc table because hci_cmd_complete_evt() assumes status = skb->data[0]
for unknown opcodes.
This leads to null-ptr-deref in cmd_sync for HCI_OP_READ_LOCAL_CODECS as
there is no hci_cc for HCI_OP_READ_LOCAL_CODECS, which always assumes
status = skb->data[0].

KASAN: null-ptr-deref in range [0x0000000000000070-0x0000000000000077]
CPU: 1 PID: 2000 Comm: kworker/u9:5 Not tainted 6.9.0-ga6bcb805883c-dirty #10
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Workqueue: hci7 hci_power_on
RIP: 0010:hci_read_supported_codecs+0xb9/0x870 net/bluetooth/hci_codec.c:138
Code: 08 48 89 ef e8 b8 c1 8f fd 48 8b 75 00 e9 96 00 00 00 49 89 c6 48 ba 00 00 00 00 00 fc ff df 4c 8d 60 70 4c 89 e3 48 c1 eb 03 <0f> b6 04 13 84 c0 0f 85 82 06 00 00 41 83 3c 24 02 77 0a e8 bf 78
RSP: 0018:ffff888120bafac8 EFLAGS: 00010212
RAX: 0000000000000000 RBX: 000000000000000e RCX: ffff8881173f0040
RDX: dffffc0000000000 RSI: ffffffffa58496c0 RDI: ffff88810b9ad1e4
RBP: ffff88810b9ac000 R08: ffffffffa77882a7 R09: 1ffffffff4ef1054
R10: dffffc0000000000 R11: fffffbfff4ef1055 R12: 0000000000000070
R13: 0000000000000000 R14: 0000000000000000 R15: ffff88810b9ac000
FS:  0000000000000000(0000) GS:ffff8881f6c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6ddaa3439e CR3: 0000000139764003 CR4: 0000000000770ef0
PKRU: 55555554
Call Trace:
 <TASK>
 hci_read_local_codecs_sync net/bluetooth/hci_sync.c:4546 [inline]
 hci_init_stage_sync net/bluetooth/hci_sync.c:3441 [inline]
 hci_init4_sync net/bluetooth/hci_sync.c:4706 [inline]
 hci_init_sync net/bluetooth/hci_sync.c:4742 [inline]
 hci_dev_init_sync net/bluetooth/hci_sync.c:4912 [inline]
 hci_dev_open_sync+0x19a9/0x2d30 net/bluetooth/hci_sync.c:4994
 hci_dev_do_open net/bluetooth/hci_core.c:483 [inline]
 hci_power_on+0x11e/0x560 net/bluetooth/hci_core.c:1015
 process_one_work kernel/workqueue.c:3267 [inline]
 process_scheduled_works+0x8ef/0x14f0 kernel/workqueue.c:3348
 worker_thread+0x91f/0xe50 kernel/workqueue.c:3429
 kthread+0x2cb/0x360 kernel/kthread.c:388
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2024-50255?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-50255?

Apply the vendor's patch.

## Is CVE-2024-50255 being exploited?

There is no known exploitation of CVE-2024-50255 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-2024-50255 and fix it if it is affected.

What it is: CVE-2024-50255 is a medium-severity vulnerability in Linux kernel, published on 9 Nov 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-2024-50255 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-2024-50255/ (Markdown: https://insights.sbomify.com/CVE-2024-50255/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-50255
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-50255
- OSV: https://osv.dev/vulnerability/CVE-2024-50255

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-50255/
Summaries are generated and may contain mistakes; the official description above is the record.