CVE-2021-0236

Due to an improper check for unusual or exceptional conditions in Juniper Networks Junos OS and Junos OS Evolved the Routing Protocol Daemon (RPD) service, upon receipt of a specific matching BGP packet meeting a specific term in the flowspec configuration, crashes and restarts causing a Denial of Service (DoS). Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. This issue affects only Multiprotocol BGP (MP-BGP) VPNv6 FlowSpec deployments. This issue affects: Juniper Networks Junos OS: 18.4 versions prior to 18.4R1-S8, 18.4R2-S7, 18.4R3-S7; 19.1 versions prior to 19.1R2-S2, 19.1R3-S4; 19.2 versions prior to 19.2R1-S6, 19.2R3-S2; 19.3 versions prior to 19.3R3-S2; 19.4 versions prior to 19.4R2-S4, 19.4R3-S1; 20.1 versions prior to 20.1R2, 20.1R3; 20.2 versions prior to 20.2R2, 20.2R3; 20.3 versions prior to 20.3R1-S1, 20.3R2. Juniper Networks Junos OS Evolved: All versions after 18.4R1-EVO prior to 20.3R2-EVO. This issue does not affect: Juniper Networks Junos OS versions prior to 18.4R1. Juniper Networks Junos OS Evolved versions prior to 18.4R1-EVO.

• CWE-754
• CWE-754

• https://kb.juniper.net/JSA11131Vendor Advisory
• https://kb.juniper.net/JSA11131Vendor Advisory

Published

Apr 22, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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