CVE-2021-0282: Improper Check for Unusual or Exceptional Conditions

On Juniper Networks Junos OS devices with Multipath or add-path feature enabled, processing a specific BGP UPDATE can lead to a routing process daemon (RPD) crash and restart, causing a Denial of Service (DoS). Continued receipt and processing of this UPDATE message will create a sustained Denial of Service (DoS) condition. This BGP UPDATE message can propagate to other BGP peers with vulnerable Junos versions on which Multipath or add-path feature is enabled, and cause RPD to crash and restart. This issue affects both IBGP and EBGP deployments in IPv4 or IPv6 network. Junos OS devices that do not have the BGP Multipath or add-path feature enabled are not affected by this issue. This issue affects: Juniper Networks Junos OS 12.3 versions prior to 12.3R12-S18; 15.1 versions prior to 15.1R7-S9; 17.3 versions prior to 17.3R3-S11; 17.4 versions prior to 17.4R2-S13, 17.4R3-S4; 18.1 versions prior to 18.1R3-S12; 18.2 versions prior to 18.2R3-S7; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R2-S6, 18.4R3-S6; 19.1 versions prior to 19.1R3-S3;