CVE-2023-53761 USB: usbtmc: Fix direction for 0-length ioctl control messages
A local attacker can trigger a kernel warning and potential denial of service by sending a malformed zero-length USB control message via ioctl.
- 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
What is CVE-2023-53761?
CVE-2023-53761 is a denial of service vulnerability in Linux, published on 8 Dec 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:
USB: usbtmc: Fix direction for 0-length ioctl control messages
The syzbot fuzzer found a problem in the usbtmc driver: When a user submits an ioctl for a 0-length control transfer, the driver does not check that the direction is set to OUT:
------------[ cut here ]------------ usb 3-1: BOGUS control dir, pipe 80000b80 doesn't match bRequestType fd WARNING: CPU: 0 PID: 5100 at drivers/usb/core/urb.c:411 usb_submit_urb+0x14a7/0x1880 drivers/usb/core/urb.c:411 Modules linked in: CPU: 0 PID: 5100 Comm: syz-executor428 Not tainted 6.3.0-syzkaller-12049-g58390c8ce1bd #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 RIP: 0010:usb_submit_urb+0x14a7/0x1880 drivers/usb/core/urb.c:411 Code: 7c 24 40 e8 1b 13 5c fb 48 8b 7c 24 40 e8 21 1d f0 fe 45 89 e8 44 89 f1 4c 89 e2 48 89 c6 48 c7 c7 e0 b5 fc 8a e8 19 c8 23 fb <0f> 0b e9 9f ee ff ff e8 ed 12 5c fb 0f b6 1d 12 8a 3c 08 31 ff 41 RSP: 0018:ffffc90003d2fb00 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff8880789e9058 RCX: 0000000000000000 RDX: ffff888029593b80 RSI: ffffffff814c1447 RDI: 0000000000000001 RBP: ffff88801ea742f8 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffff88802915e528 R13: 00000000000000fd R14: 0000000080000b80 R15: ffff8880222b3100 FS: 0000555556ca63c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9ef4d18150 CR3: 0000000073e5b000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> usb_start_wait_urb+0x101/0x4b0 drivers/usb/core/message.c:58 usb_internal_control_msg drivers/usb/core/message.c:102 [inline] usb_control_msg+0x320/0x4a0 drivers/usb/core/message.c:153 usbtmc_ioctl_request drivers/usb/class/usbtmc.c:1954 [inline] usbtmc_ioctl+0x1b3d/0x2840 drivers/usb/class/usbtmc.c:2097
To fix this, we must override the direction in the bRequestType field of the control request structure when the length is 0.
Which versions are affected by CVE-2023-53761?
How do I fix CVE-2023-53761?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2023-53761 being exploited?
There is no known exploitation of CVE-2023-53761 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-53761, DEBIAN-CVE-2023-53761, GHSA-8x9m-r5f2-8m89, UBUNTU-CVE-2023-53761.