SB20260918391 - Use-after-free in Linux kernel md driver
Published: September 18, 2026
Security Bulletin ID
SB20260918391
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Information disclosure
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Use-after-free (CVE-ID: CVE-2026-90278)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 0 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a local user to trigger use-after-free access to llbitmap storage.
The vulnerability exists due to incorrect teardown ordering in the md bitmap teardown path when stopping an md device configured with llbitmap while RAID1 behind-write completions are pending. A local user can stop an affected md device while RAID1 behind-write completions are pending to trigger use-after-free access to llbitmap storage.
Remediation
Install update from vendor's website.