A Deadlock vulnerability in the packet forwarding engine (PFE) of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial of Service (DoS). When a large amount of traffic is processed by ATP Cloud inspection, a deadlock can occur which will result in a PFE crash and restart. Whether the crash occurs, depends on system internal timing that is outside the attackers control. This issue affects Junos OS on SRX Series: * All versions before 21.3R3-S1, * 21.4 versions before 21.4R3, * 22.1 versions before 22.1R2, * 22.2 versions before 22.2R1-S2, 22.2R2.