CVE-2026-90216 ubi: Fix rollback for explicit UBI device numbers
A logic error in Linux kernel UBI initialization rollback can cause resource leaks or instability when explicit device numbers are used, requiring local privileged access.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-90216?
CVE-2026-90216 is a vulnerability in Linux, published on 17 Sep 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:
ubi: Fix rollback for explicit UBI device numbers
ubi_init_attach() rolls back module initialization failures by scanning ubi_devices[0..i-1], where i is the mtd= parameter index. That assumes the parameter index matches the UBI device number.
That assumption is not true when mtd= specifies an explicit ubi_num. A successfully attached device can be stored at a higher ubi_devices[] slot, and a later failure can miss it during rollback.
Scan the full ubi_devices[] array and detach by the actual array index, matching the way UBI devices are stored.
Which versions are affected by CVE-2026-90216?
How do I fix CVE-2026-90216?
Apply the vendor's patch.
Is CVE-2026-90216 being exploited?
There is no known exploitation of CVE-2026-90216 in the wild and no public exploit code.
Sources
Also known as AZL-102449, BELL-CVE-2026-90216, DEBIAN-CVE-2026-90216, GHSA-98x6-774g-8659, UBUNTU-CVE-2026-90216.