CVE-2026-68162

CVE-2026-68162 is a use-after-free vulnerability found within the Stream Control Transmission Protocol (SCTP) implementation of the Linux kernel. The flaw specifically resides in the `proc_sctp_do_auth()` function, which is responsible for updating the SCTP control socket when the `net.sctp.auth_enable` sysctl parameter is modified. This issue arises because an already opened sysctl file can reference a network namespace during its teardown, leading to improper ordering of sysctl registration and control socket lifecycle. The vulnerability creates two race windows: one during initialization where `auth_enable` can be written before the control socket exists, and another during teardown where `auth_enable` remains writable after the control socket has been released. A local attacker who holds an open file descriptor to the `auth_enable` sysctl can trigger this use-after-free condition on the SCTP control socket during network namespace teardown. This can potentially lead to memory corruption or a system crash.