SB2026091925 - Memory leak in Linux kernel block null_blk driver
Published: September 19, 2026
Security Bulletin ID
SB2026091925
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Partial DoS
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Memory leak (CVE-ID: CVE-2026-90188)
CWE-ID: CWE-401 - Missing release of memory after effective lifetime
CVSSv4: 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]
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.
Remediation
Install update from vendor's website.
References
- 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