A vulnerability in the processing of specific MPLS packets in Juniper Networks Junos OS on MX Series and EX9200 Series devices with Trio-based MPCs (Modular Port Concentrators) may cause FPC to crash and lead to a Denial of Service (DoS) condition. Continued receipt of this packet will sustain the Denial of Service (DoS) condition. This issue only affects MX Series and EX9200 Series with Trio-based PFEs (Packet Forwarding Engines). This issue affects Juniper Networks Junos OS on MX Series, EX9200 Series: 17.3 versions prior to 17.3R3-S12.

17.4 versions prior to 17.4R2-S13, 17.4R3-S5.

18.1 versions prior to 18.1R3-S13.

18.2 versions prior to 18.2R3-S8.

18.3 versions prior to 18.3R3-S5.

18.4 versions prior to 18.4R2-S8, 18.4R3-S8.

19.1 versions prior to 19.1R3-S5.

19.2 versions prior to 19.2R3-S2.

19.3 versions prior to 19.3R2-S6, 19.3R3-S3.

19.4 versions prior to 19.4R1-S4, 19.4R2-S4, 19.4R3-S2.

20.1 versions prior to 20.1R3.

20.2 versions prior to 20.2R2-S2, 20.2R3.

20.3 versions prior to 20.3R2.

20.4 versions prior to 20.4R2;.