Use-after-free in Linux kernel - CVE-2026-63927
Published: July 20, 2026
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to use-after-free in the dwc2 USB host controller driver debug code when dequeuing a usb request block and logging its status after calling usb_hcd_giveback_urb(). A local user can trigger URB handling to cause a denial of service.
The issue occurs in debug logging within the _dwc2_hcd_urb_dequeue() path.
Affected software
Ubuntu
linux-ibm (Ubuntu package)
linux-azure (Ubuntu package)
linux-aws (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-nvidia-bos (Ubuntu package)
How to mitigate CVE-2026-63927
linux-ibm (Ubuntu package) - addressed in versions 7.0.0-1008.8, 7.0.0-1010.10
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1010.10
linux-aws (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1015.15
linux-nvidia (Ubuntu package) - addressed in versions 7.0.0-1016.16, 7.0.0-1016.16~24.04.1
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2016.16
External References
- https://git.kernel.org/stable/c/0584af4fe40fa5e254a05d69ce658746de641708
- https://git.kernel.org/stable/c/63b0dafa676aad4d0c3f01a61ad8e2990907660c
- https://git.kernel.org/stable/c/6d0b79d1d1118145e48a68192b6d733e39387053
- https://git.kernel.org/stable/c/84ea928ed584756e59c6ac09736f12d1db95ded0
- https://git.kernel.org/stable/c/9ea06a3fbf9f16e0d98c52cb3b99642be15ec281
- https://git.kernel.org/stable/c/9fe1d84f7e2cf33634e8afb7f4b7f8de182dd913
- https://git.kernel.org/stable/c/a15eeeceb94cbc04edef395e4d777ff554bdc27d
- https://git.kernel.org/stable/c/d5fc183ed614aeba6779cc992325be560f9a4451