Juniper Junos CVE-2019-0051 Denial of Service Vulnerability



Date Discovered

October 9, 2019


Juniper Junos is prone to a denial-of-service vulnerability. An attacker may exploit this issue to cause denial-of-service conditions. The following versions of Junos on Juniper SRX5000 Series devices are vulnerable: Juniper Junos 12.3X48 versions prior to 12.3X48-D85 Juniper Junos 15.1X49 versions prior to 15.1X49-D180 Juniper Junos 17.3 versions prior to 17.3R3-S7 Juniper Junos 17.4 versions prior to 17.4R2-S6 and 17.4R3 Juniper Junos 18.1 versions prior to 18.1R3-S8 Juniper Junos 18.2 versions prior to 18.2R3 Juniper Junos 18.3 versions prior to 18.3R2 Juniper Junos 18.4 versions prior to 18.4R2 Juniper Junos 19.1 versions prior to 19.1R2

Technologies Affected

  • Juniper Junos 12.3X48
  • Juniper Junos 15.1X49
  • Juniper Junos 17.3
  • Juniper Junos 17.4
  • Juniper Junos 18.1
  • Juniper Junos 18.2
  • Juniper Junos 18.3
  • Juniper Junos 18.4
  • Juniper Junos 19.1
  • Juniper SRX5000 Series


Block external access at the network boundary, unless external parties require service.
If global access isn't needed, block access at the network perimeter to computers hosting the vulnerable device.

Deploy network intrusion detection systems to monitor network traffic for malicious activity.
Deploy NIDS to monitor network traffic for signs of anomalous or suspicious activity such as unexplained incoming and outgoing traffic. This may indicate exploit attempts or activity that results from successful exploits.

Do not follow links provided by unknown or untrusted sources.
To reduce the likelihood of successful exploits, never visit sites of questionable integrity or follow links provided by unfamiliar or untrusted sources.

Updates are available. Please see the references or vendor advisory for more information.



The vendor reported this issue.

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