CVE-2024-36009

Medium

In the Linux kernel, the following vulnerability has been resolved: ax25: Fix netdev refcount issue The dev_tracker is added to ax25_cb in ax25_bind(). When the ax25 device is detaching, the dev_tracker of ax25_cb should be deallocated in ax25_kill_by_device() instead of the dev_tracker of ax25_dev. The log reported by ref_tracker is shown below: [ 80.884935] ref_tracker: reference already released. [ 80.885150] ref_tracker: allocated in: [ 80.885349] ax25_dev_device_up+0x105/0x540 [ 80.885730] ax25_device_event+0xa4/0x420 [ 80.885730] notifier_call_chain+0xc9/0x1e0 [ 80.885730] __dev_notify_flags+0x138/0x280 [ 80.885730] dev_change_flags+0xd7/0x180 [ 80.885730] dev_ifsioc+0x6a9/0xa30 [ 80.885730] dev_ioctl+0x4d8/0xd90 [ 80.885730] sock_do_ioctl+0x1c2/0x2d0 [ 80.885730] sock_ioctl+0x38b/0x4f0 [ 80.885730] __se_sys_ioctl+0xad/0xf0 [ 80.885730] do_syscall_64+0xc4/0x1b0 [ 80.885730] entry_SYSCALL_64_after_hwframe+0x67/0x6f [ 80.885730] ref_tracker: freed in: [ 80.885730] ax25_device_event+0x272/0x420 [ 80.885730] notifier_call_chain+0xc9/0x1e0 [ 80.885730] dev_close_many+0x272/0x370 [ 80.885730] unregister_netdevice_many_notify+0x3b5/0x1180 [ 80.885730] unregister_netdev+0xcf/0x120 [ 80.885730] sixpack_close+0x11f/0x1b0 [ 80.885730] tty_ldisc_kill+0xcb/0x190 [ 80.885730] tty_ldisc_hangup+0x338/0x3d0 [ 80.885730] __tty_hangup+0x504/0x740 [ 80.885730] tty_release+0x46e/0xd80 [ 80.885730] __fput+0x37f/0x770 [ 80.885730] __x64_sys_close+0x7b/0xb0 [ 80.885730] do_syscall_64+0xc4/0x1b0 [ 80.885730] entry_SYSCALL_64_after_hwframe+0x67/0x6f [ 80.893739] ------------[ cut here ]------------ [ 80.894030] WARNING: CPU: 2 PID: 140 at lib/ref_tracker.c:255 ref_tracker_free+0x47b/0x6b0 [ 80.894297] Modules linked in: [ 80.894929] CPU: 2 PID: 140 Comm: ax25_conn_rel_6 Not tainted 6.9.0-rc4-g8cd26fd90c1a #11 [ 80.895190] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qem4 [ 80.895514] RIP: 0010:ref_tracker_free+0x47b/0x6b0 [ 80.895808] Code: 83 c5 18 4c 89 eb 48 c1 eb 03 8a 04 13 84 c0 0f 85 df 01 00 00 41 83 7d 00 00 75 4b 4c 89 ff 9 [ 80.896171] RSP: 0018:ffff888009edf8c0 EFLAGS: 00000286 [ 80.896339] RAX: 1ffff1100141ac00 RBX: 1ffff1100149463b RCX: dffffc0000000000 [ 80.896502] RDX: 0000000000000001 RSI: 0000000000000246 RDI: ffff88800a0d6518 [ 80.896925] RBP: ffff888009edf9b0 R08: ffff88806d3288d3 R09: 1ffff1100da6511a [ 80.897212] R10: dffffc0000000000 R11: ffffed100da6511b R12: ffff88800a4a31d4 [ 80.897859] R13: ffff88800a4a31d8 R14: dffffc0000000000 R15: ffff88800a0d6518 [ 80.898279] FS: 00007fd88b7fe700(0000) GS:ffff88806d300000(0000) knlGS:0000000000000000 [ 80.899436] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 80.900181] CR2: 00007fd88c001d48 CR3: 000000000993e000 CR4: 00000000000006f0 ... [ 80.935774] ref_tracker: sp%d@000000000bb9df3d has 1/1 users at [ 80.935774] ax25_bind+0x424/0x4e0 [ 80.935774] __sys_bind+0x1d9/0x270 [ 80.935774] __x64_sys_bind+0x75/0x80 [ 80.935774] do_syscall_64+0xc4/0x1b0 [ 80.935774] entry_SYSCALL_64_after_hwframe+0x67/0x6f Change ax25_dev->dev_tracker to the dev_tracker of ax25_cb in order to mitigate the bug.

Package Linux Kernel
Published 2024-05-20
Last modified 2025-09-23
CVSS version 3.1
Patch available
Awaiting data

CVSS 3.1 score

5.5

out of 10
Medium
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
High
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References

The following references provide additional information about CVE-2024-36009 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Frequently asked questions

  • What is CVE-2024-36009?

    CVE-2024-36009 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . CVE-2024-36009 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2024-36009?

    CVE-2024-36009 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H .

  • Is there a patch available for CVE-2024-36009?

    No patch is currently available for CVE-2024-36009. Monitor the NIST NVD and your Linux distribution's security advisories for updates.

  • Is CVE-2024-36009 actively exploited?

    No — CVE-2024-36009 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.