SB20260727190 - Double free in Linux kernel smb client
Published: July 27, 2026
Security Bulletin ID
SB20260727190
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote 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-2026-64383)
CWE-ID: CWE-415 - Double Free
CVSSv4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote user to cause a denial of service.
The vulnerability exists due to double free in SMB2_flush() when handling replay attempts for flush responses. A remote user can trigger a replayable flush response followed by a failed retry to cause a denial of service.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/013a9a3da46c5dabcf18f65ea6a47874ba12a15d
- https://git.kernel.org/stable/c/3407240cde132a4b72d6429a2625a09a2f78adaf
- https://git.kernel.org/stable/c/4be31c943a3a27a5a0251dbb8f5cb89059ec3d5a
- https://git.kernel.org/stable/c/6e27f40b682a5e42a2daae3ce6d96f0e0e16dedb
- https://git.kernel.org/stable/c/878757163eea684750107a31ea134c103863515d