# CVE-2022-49111: Bluetooth: Fix use after free in hci_send_acl

> A use-after-free vulnerability in the Linux kernel Bluetooth subsystem allows attackers to cause denial of service or potentially execute code via crafted HCI events.

- **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-2022-49111, GHSA-5wpf-jxv5-j2rg, UBUNTU-CVE-2022-49111

## What is CVE-2022-49111?

CVE-2022-49111 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: Fix use after free in hci_send_acl

This fixes the following trace caused by receiving
HCI_EV_DISCONN_PHY_LINK_COMPLETE which does call hci_conn_del without
first checking if conn->type is in fact AMP_LINK and in case it is
do properly cleanup upper layers with hci_disconn_cfm:

 ==================================================================
    BUG: KASAN: use-after-free in hci_send_acl+0xaba/0xc50
    Read of size 8 at addr ffff88800e404818 by task bluetoothd/142

    CPU: 0 PID: 142 Comm: bluetoothd Not tainted
    5.17.0-rc5-00006-gda4022eeac1a #7
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
    rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
    Call Trace:
     <TASK>
     dump_stack_lvl+0x45/0x59
     print_address_description.constprop.0+0x1f/0x150
     kasan_report.cold+0x7f/0x11b
     hci_send_acl+0xaba/0xc50
     l2cap_do_send+0x23f/0x3d0
     l2cap_chan_send+0xc06/0x2cc0
     l2cap_sock_sendmsg+0x201/0x2b0
     sock_sendmsg+0xdc/0x110
     sock_write_iter+0x20f/0x370
     do_iter_readv_writev+0x343/0x690
     do_iter_write+0x132/0x640
     vfs_writev+0x198/0x570
     do_writev+0x202/0x280
     do_syscall_64+0x38/0x90
     entry_SYSCALL_64_after_hwframe+0x44/0xae
    RSP: 002b:00007ffce8a099b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
    Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3
    0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 14 00 00 00 0f 05
    <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
    RDX: 0000000000000001 RSI: 00007ffce8a099e0 RDI: 0000000000000015
    RAX: ffffffffffffffda RBX: 00007ffce8a099e0 RCX: 00007f788fc3cf77
    R10: 00007ffce8af7080 R11: 0000000000000246 R12: 000055e4ccf75580
    RBP: 0000000000000015 R08: 0000000000000002 R09: 0000000000000001
    </TASK>
    R13: 000055e4ccf754a0 R14: 000055e4ccf75cd0 R15: 000055e4ccf4a6b0

    Allocated by task 45:
        kasan_save_stack+0x1e/0x40
        __kasan_kmalloc+0x81/0xa0
        hci_chan_create+0x9a/0x2f0
        l2cap_conn_add.part.0+0x1a/0xdc0
        l2cap_connect_cfm+0x236/0x1000
        le_conn_complete_evt+0x15a7/0x1db0
        hci_le_conn_complete_evt+0x226/0x2c0
        hci_le_meta_evt+0x247/0x450
        hci_event_packet+0x61b/0xe90
        hci_rx_work+0x4d5/0xc50
        process_one_work+0x8fb/0x15a0
        worker_thread+0x576/0x1240
        kthread+0x29d/0x340
        ret_from_fork+0x1f/0x30

    Freed by task 45:
        kasan_save_stack+0x1e/0x40
        kasan_set_track+0x21/0x30
        kasan_set_free_info+0x20/0x30
        __kasan_slab_free+0xfb/0x130
        kfree+0xac/0x350
        hci_conn_cleanup+0x101/0x6a0
        hci_conn_del+0x27e/0x6c0
        hci_disconn_phylink_complete_evt+0xe0/0x120
        hci_event_packet+0x812/0xe90
        hci_rx_work+0x4d5/0xc50
        process_one_work+0x8fb/0x15a0
        worker_thread+0x576/0x1240
        kthread+0x29d/0x340
        ret_from_fork+0x1f/0x30

    The buggy address belongs to the object at ffff88800c0f0500
    The buggy address is located 24 bytes inside of
    which belongs to the cache kmalloc-128 of size 128
    The buggy address belongs to the page:
    128-byte region [ffff88800c0f0500, ffff88800c0f0580)
    flags: 0x100000000000200(slab|node=0|zone=1)
    page:00000000fe45cd86 refcount:1 mapcount:0
    mapping:0000000000000000 index:0x0 pfn:0xc0f0
    raw: 0000000000000000 0000000080100010 00000001ffffffff
    0000000000000000
    raw: 0100000000000200 ffffea00003a2c80 dead000000000004
    ffff8880078418c0
    page dumped because: kasan: bad access detected
    ffff88800c0f0400: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc
    Memory state around the buggy address:
    >ffff88800c0f0500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
    ffff88800c0f0480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
    ffff88800c0f0580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   
---truncated---

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2022-49111?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-49111?

Apply the vendor's patch.

## Is CVE-2022-49111 being exploited?

There is no known exploitation of CVE-2022-49111 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-2022-49111 and fix it if it is affected.

What it is: CVE-2022-49111 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-2022-49111 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-2022-49111/ (Markdown: https://insights.sbomify.com/CVE-2022-49111/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-49111
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-49111
- OSV: https://osv.dev/vulnerability/CVE-2022-49111

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-49111/
Summaries are generated and may contain mistakes; the official description above is the record.
