An Improper Authentication vulnerability in the kernel of Juniper Networks Junos OS allows an unauthenticated, network-based attacker to cause an impact on confidentiality or integrity. A vulnerability in the processing of TCP-AO will allow a BGP or LDP peer not configured with authentication to establish a session even if the peer is locally configured to use authentication. This could lead to untrusted or unauthorized sessions being established. This issue affects Juniper Networks Junos OS: 21.2 versions prior to 21.2R3-S1; 21.3 versions prior to 21.3R2-S2, 21.3R3; 21.4 versions prior to 21.4R2-S1, 21.4R3; 22.1 versions prior to 22.1R1-S1, 22.1R2. This issue does not affect Juniper Networks Junos OS Evolved.