SB20260727177 - Double free in Linux kernel smb client
Published: July 27, 2026
Security Bulletin ID
SB20260727177
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Double free (CVE-ID: CVE-2026-64387)
CWE-ID: CWE-415 - Double Free
CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a double free in SMB2_query_directory in the SMB client when handling replayed query directory responses and reinitialization failures. A local user can trigger a replayable error and subsequent cleanup conditions to cause a denial of service.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/00b0fa425941438b664950a8ee65dfba2def4336
- https://git.kernel.org/stable/c/1665f25b1dea30bf2d02e16245d203a944c9d994
- https://git.kernel.org/stable/c/3317a5d015fca976475aa71df224056777316fde
- https://git.kernel.org/stable/c/3409aedf3c81a810243da94164f6621c9d205c98
- https://git.kernel.org/stable/c/9647492b5e41954be59d5157eddbcd4cdc1656f7