CVE-2026-68369 usb: gadget: printer: fix infinite loop in printer_read()
A local attacker can cause an infinite loop in the Linux kernel USB printer gadget driver by triggering a copy_to_user failure, leading to denial of service.
- 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-2026-68369?
CVE-2026-68369 is a denial of service vulnerability in Linux, published on 10 Aug 2026. 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: gadget: printer: fix infinite loop in printer_read()
printer_read() uses the same variable for the requested copy size and the number of bytes actually copied to user space. copy_to_user() returns the number of bytes not copied, so when it fails to copy anything, the computed copied length becomes zero.
In that case len, buf, current_rx_bytes and current_rx_buf are left unchanged. If RX data is available and the user buffer remains unwritable, the read loop can repeat indefinitely.
Track the copied length separately and return -EFAULT, or the number of bytes already copied, if an iteration makes no progress.
Which versions are affected by CVE-2026-68369?
How do I fix CVE-2026-68369?
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-2026-68369 being exploited?
There is no known exploitation of CVE-2026-68369 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-68369, DEBIAN-CVE-2026-68369, GHSA-6mcx-v8qc-xx8r, UBUNTU-CVE-2026-68369.