CVE-2026-98757 usb: cdns3: fix use-after-free in cdns3_gadget_exit()
A use-after-free in the Linux kernel's cdns3 USB gadget driver allows local attackers to execute arbitrary code or escalate privileges.
- 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-2026-98757?
CVE-2026-98757 is an use after free vulnerability in Linux, published on 18 Oct 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: cdns3: fix use-after-free in cdns3_gadget_exit()
cdns3_gadget_start() arms two works on system_freezable_wq: pending_status_wq for the deferred ep0 status stage and aligned_buf_wq for realigned request buffers. Both handlers use the cdns3_device the works are embedded in, and cdns3_pending_setup_status_handler() also calls the ep0 request completion.
cdns3_gadget_exit() does not wait for these works. It frees all endpoints and aligned buffers and drops the last reference to the gadget device, which frees priv_dev, so a work queued before the exit can run after the free.
Fix this by waiting for both works after the gadget driver is unbound and the IRQ is freed, when no new work can be queued, and before the endpoints and buffers are released.
This issue was found by an in-house static analysis tool.
Which versions are affected by CVE-2026-98757?
How do I fix CVE-2026-98757?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-98757 being exploited?
There is no known exploitation of CVE-2026-98757 in the wild and no public exploit code.
Sources
Also known as AZL-108936, BELL-CVE-2026-98757, DEBIAN-CVE-2026-98757, GHSA-cfx2-v35h-c74w, UBUNTU-CVE-2026-98757.