SB2026072835 - Use-after-free in Linux kernel smc
Published: July 28, 2026
Security Bulletin ID
SB2026072835
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) Use-after-free (CVE-ID: CVE-2026-64541)
CWE-ID: CWE-416 - Use After 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 use-after-free in smc_cdc_rx_handler() when handling SMC-R CDC messages for a connection after releasing conns_lock. A local user can trigger a concurrent socket close while the handler continues to dereference the freed socket to cause a denial of service.
Only SMC-R is affected.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/1951bffbc6493ec34cff3956b29d4bc6606904a6
- https://git.kernel.org/stable/c/3bfb96d9bc6a7ed0b99c7db329cc2e22a28d84bb
- https://git.kernel.org/stable/c/472e9d7c0d5b03be3ff91ff941f57da822b031bc
- https://git.kernel.org/stable/c/647b19e5cc145a2f1f685ae8ff3805a17356888c
- https://git.kernel.org/stable/c/8145b432136285e01091815b48ceb2dae261f262
- https://git.kernel.org/stable/c/8de4f665d0febfb92803dece377791a563fc7041
- https://git.kernel.org/stable/c/9d160b35cc34a2ba8229d07651468a7848325135
- https://git.kernel.org/stable/c/ce5aa8084329351086894aa34d77e40301d5bd3d