CVE-2026-90216

About vulnerability

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.

Affected product:

AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Debian 10 ELS , Debian 11 ELS , Oracle Linux 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS

Affected packages:

linux @ 5.4.0 (+13 more)

Live-patch status from KernelCare for each operating system.