Use-after-free in Linux kernel - CVE-2026-90189
Published: September 19, 2026
Vulnerability identifier: #VU151295
CSH Severity: Low
CVSS v4: 0 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-90189
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to trigger a use-after-free condition.
The vulnerability exists due to a use-after-free in the null_blk err_dev cleanup path when accessing a configfs item that remains reachable after cleanup. A local user can access the reachable configfs item to trigger a use-after-free condition.
Exploitation requires a racing user-created device to be added to the device list before module initialization enters error cleanup.
Affected software
Linux kernel
How to mitigate CVE-2026-90189
Install security update from vendor's repository.
External References
- https://git.kernel.org/stable/c/2679b11e9256bd70a5ef41783bab6ad6c34a3db1
- https://git.kernel.org/stable/c/57debc907aef66319d244009d3370dcd97388d37
- https://git.kernel.org/stable/c/c9d293d6bb0575fcb1f3408129453187e2a28a4e
- https://git.kernel.org/stable/c/cab9bf5f68f76cd44e0ec92bd4a60c9b83656a36
- https://git.kernel.org/stable/c/d761be1b8f2bbabc41252deb79a426d3f0d4fa10
- https://git.kernel.org/stable/c/dbcedbe4819ae21274ea77469e61e46a878b9943