SB20260912134 - Memory leak in Linux kernel btrfs
Published: September 12, 2026
Security Bulletin ID
SB20260912134
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-2026-89644)
CWE-ID: CWE-401 - Missing release of memory after effective lifetime
CVSSv4: 2 [CVSS:4.0/AV:L/AC:L/AT:P/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 resource leak.
The vulnerability exists due to missing release of memory after effective lifetime in btrfs_get_blocks_direct_write() when performing a direct I/O write to a NOCOW range and ordered extent allocation fails. A local user can issue a direct I/O write to a NOCOW range to cause a resource leak.
Remediation
Install update from vendor's website.