# CVE-2022-49470: Bluetooth: btmtksdio: fix use-after-free at btmtksdio_recv_event

> A use-after-free vulnerability in the Linux kernel's Bluetooth driver allows attackers to cause a denial of service or potentially execute code.

- **Severity:** High 8.8 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 26 Feb 2025
- **Updated:** 5 Aug 2026
- **Also known as:** DEBIAN-CVE-2022-49470, GHSA-3r4m-vx24-mm6m, ROOT-OS-DEBIAN-11-CVE-2022-49470, UBUNTU-CVE-2022-49470

## What is CVE-2022-49470?

CVE-2022-49470 is a high-severity use after free vulnerability in Linux kernel, published on 26 Feb 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:

Bluetooth: btmtksdio: fix use-after-free at btmtksdio_recv_event

We should not access skb buffer data anymore after hci_recv_frame was
called.

[   39.634809] BUG: KASAN: use-after-free in btmtksdio_recv_event+0x1b0
[   39.634855] Read of size 1 at addr ffffff80cf28a60d by task kworker
[   39.634962] Call trace:
[   39.634974]  dump_backtrace+0x0/0x3b8
[   39.634999]  show_stack+0x20/0x2c
[   39.635016]  dump_stack_lvl+0x60/0x78
[   39.635040]  print_address_description+0x70/0x2f0
[   39.635062]  kasan_report+0x154/0x194
[   39.635079]  __asan_report_load1_noabort+0x44/0x50
[   39.635099]  btmtksdio_recv_event+0x1b0/0x1c4
[   39.635129]  btmtksdio_txrx_work+0x6cc/0xac4
[   39.635157]  process_one_work+0x560/0xc5c
[   39.635177]  worker_thread+0x7ec/0xcc0
[   39.635195]  kthread+0x2d0/0x3d0
[   39.635215]  ret_from_fork+0x10/0x20
[   39.635247] Allocated by task 0:
[   39.635260] (stack is not available)
[   39.635281] Freed by task 2392:
[   39.635295]  kasan_save_stack+0x38/0x68
[   39.635319]  kasan_set_track+0x28/0x3c
[   39.635338]  kasan_set_free_info+0x28/0x4c
[   39.635357]  ____kasan_slab_free+0x104/0x150
[   39.635374]  __kasan_slab_free+0x18/0x28
[   39.635391]  slab_free_freelist_hook+0x114/0x248
[   39.635410]  kfree+0xf8/0x2b4
[   39.635427]  skb_free_head+0x58/0x98
[   39.635447]  skb_release_data+0x2f4/0x410
[   39.635464]  skb_release_all+0x50/0x60
[   39.635481]  kfree_skb+0xc8/0x25c
[   39.635498]  hci_event_packet+0x894/0xca4 [bluetooth]
[   39.635721]  hci_rx_work+0x1c8/0x68c [bluetooth]
[   39.635925]  process_one_work+0x560/0xc5c
[   39.635951]  worker_thread+0x7ec/0xcc0
[   39.635970]  kthread+0x2d0/0x3d0
[   39.635990]  ret_from_fork+0x10/0x20
[   39.636021] The buggy address belongs to the object at ffffff80cf28a600
                which belongs to the cache kmalloc-512 of size 512
[   39.636039] The buggy address is located 13 bytes inside of
                512-byte region [ffffff80cf28a600, ffffff80cf28a800)

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2022-49470?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-49470?

Apply the vendor's patch.

## Is CVE-2022-49470 being exploited?

There is no known exploitation of CVE-2022-49470 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-2022-49470 and fix it if it is affected.

What it is: CVE-2022-49470 is a high-severity use after free vulnerability in Linux kernel, published on 26 Feb 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-2022-49470 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-2022-49470/ (Markdown: https://insights.sbomify.com/CVE-2022-49470/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-49470
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-49470
- OSV: https://osv.dev/vulnerability/CVE-2022-49470

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-49470/
Summaries are generated and may contain mistakes; the official description above is the record.
