CVE-2026-53236

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A side-channel issue exists where an unprivileged application can attach a filter to TCP sockets to leak TCP sequence and acknowledgment numbers. This is achieved through the use of SO ATTACH FILTER (cBPF), which allows the attachment of classic Berkeley Packet Filters to sockets.

Recommendations Restrict the use of SO ATTACH FILTER on TCP sockets to users with CAP NET ADMIN capability.