SB20260918346 - Unchecked Return Value in Linux kernel block driver

Description

This security bulletin contains information about 1 vulnerability.

1) Unchecked Return Value (CVE-ID: CVE-2026-90324)

CWE-ID: CWE-252 - Unchecked Return Value

CVSSv4: 0 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a local user to trigger I/O processing with an uninitialized iov_iter.

The vulnerability exists due to an unchecked return value in the ublk_map_io and ublk_unmap_io functions when processing an I/O buffer address supplied by a userspace ublk server. A local user can operate a userspace ublk server and provide an address range outside the allowed user address space to trigger I/O processing with an uninitialized iov_iter.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/0121c84adb6a4cd6f7560b5895bd88f9899bbc1f
• https://git.kernel.org/stable/c/3831568792af75b6523fa93bb91560e29189cf55
• https://git.kernel.org/stable/c/5ac6019cb78e98c9608fda72726b36ddf8474dd7