Skip to main content
← All vulnerabilities
CVE-2021-31363

Junos OS and Junos OS Evolved: Receipt of a specific LDP message will cause a Denial of Service

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 19.2R3-S3, 20.1R2-S3-EVO, 20.3R1-S2-EVO
None on Exploit-DB, Metasploit or GitHub

Summary

In an MPLS P2MP environment a Loop with Unreachable Exit Condition vulnerability in the routing protocol daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker to cause high load on RPD which in turn may lead to routing protocol flaps. If a system with sensor-based-stats enabled receives a specific LDP FEC this can lead to the above condition. Continued receipted of such an LDP FEC will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS 19.2 version 19.2R2 and later versions prior to 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S2; 19.4 versions prior to 19.4R1-S4, 19.4R2-S4, 19.4R3-S2; 20.1 versions prior to 20.1R2-S1, 20.1R3; 20.2 versions prior to 20.2R2-S1, 20.2R3; 20.3 versions prior to 20.3R1-S2, 20.3R2. This issue does not affect Juniper Networks Junos OS versions prior to 19.2R2. Juniper Networks Junos OS Evolved All versions prior to 20.1R2-S3-EVO; 20.3 versions prior to 20.3R1-S2-EVO.

Timeline

  1. CVE published
  2. Record last updated

Affected versions

  • Juniper Networks Junos OS

    From 19.2R2 · fixed in 19.2R3-S3

  • Juniper Networks Junos OS Evolved

    fixed in 20.1R2-S3-EVO; From 20.3 · fixed in 20.3R1-S2-EVO

References 1

kb.juniper.net