SB2026081639 - Off-by-one in Linux kernel core lag driver
Published: August 16, 2026
Security Bulletin ID
SB2026081639
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) Off-by-one (CVE-ID: CVE-2026-72345)
CWE-ID: CWE-193 - Off-by-one Error
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 an off-by-one error in mlx5_lag_create_single_fdb() rollback logic when handling error rollback during single-FDB creation. A local user can trigger a failure during single-FDB creation to cause a denial of service.
The reverse cleanup loop may operate on uninitialized state or double-tear-down a rule that was already rolled back.
Remediation
Install update from vendor's website.