Memory leak in Linux kernel - CVE-2026-90188

Vulnerability identifier: #VU151293

CSH Severity: Low

CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-90188

CWE-ID: CWE-401

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a memory leak in the null_blk module initialization error path when initializing null_blk with shared_tags enabled and device creation fails. A local user can trigger null_blk module initialization under these conditions to cause a denial of service.

Linux kernel
Debian Linux
Ubuntu
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (Ubuntu package)
linux-ibm (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux (Debian package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux (Ubuntu package) - update to 7.0.0-42.42
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-ibm (Ubuntu package) - update to 7.0.0-1017.17
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17
linux (Debian package) - update to 6.12.111-1

• https://git.kernel.org/stable/c/081cf37e8a0e00cd91d6df53172c9d928790a798
• https://git.kernel.org/stable/c/0b2faa330184340d9418ad2c627c2ae881772e33
• https://git.kernel.org/stable/c/2882e1450fa4597811a951196e07553ea134eb31
• https://git.kernel.org/stable/c/2b59484ac1e64dd78dbe8c6140891c6308085a75
• https://git.kernel.org/stable/c/5a1c5ff3a49ba93a1fd0b70537e7a0164071760d
• https://git.kernel.org/stable/c/665c94554ff0d5d88caae7f40c16c8e0a3369eda

• Memory leak in Linux kernel block null_blk driver
• Debian update for linux
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more