NULL pointer dereference in Linux kernel - CVE-2026-90066
Published: September 19, 2026
Vulnerability details
The vulnerability allows a local privileged user to cause a denial of service.
The vulnerability exists due to improper validation of an error pointer in ftrace_direct_multi_init() and ftrace_direct_multi_exit() in samples/ftrace/ftrace-direct-multi-modify.c when unloading the ftrace-direct-multi-modify module after kthread_run() fails. A local privileged user can cause kthread_stop() to receive an error pointer to cause a denial of service.
Affected software
How to mitigate CVE-2026-90066
External References
- https://git.kernel.org/stable/c/626614df9080d7052fbe24dc90b5434717ab7a9f
- https://git.kernel.org/stable/c/6727b7618f49401acf373fa3ec5712e2ec52e5cf
- https://git.kernel.org/stable/c/7a96b9f6d5ba23dbce66c8a4a242effd4c01a830
- https://git.kernel.org/stable/c/98b7b2a29ae87937aa02ab9391543ef8c602cd94
- https://git.kernel.org/stable/c/cf839636911d8313f3ecd098329fd0b96499e4cf