Support Support Downloads Knowledge Base Case Manager My Juniper Community

Knowledge Base

Search our Knowledge Base sites to find answers to your questions.

Ask All Knowledge Base Sites All Knowledge Base Sites JunosE Defect (KA)Knowledge BaseSecurity AdvisoriesTechnical BulletinsTechnotes Sign in to display secure content and recently viewed articles

2020-10 Security Bulletin: Junos OS: EX2300 Series: High CPU load due to receipt of specific multicast packets on layer 2 interface (CVE-2020-1668)

0

0

Article ID: JSA11065 SECURITY_ADVISORIES Last Updated: 14 Oct 2020Version: 1.0
Product Affected:
This issue affects Junos OS 18.1, 18.2, 18.3, 18.4, 19.1, 19.2, 19.3, 19.4, 20.1. Affected platforms: EX2300 Series.
Problem:

On Juniper Networks EX2300 Series, receipt of a stream of specific multicast packets by the layer2 interface can cause high CPU load, which could lead to traffic interruption.

This issue occurs when multicast packets are received by the layer 2 interface.

To check if the device has high CPU load due to this issue, the administrator can issue the following command:

user@host> show chassis routing-engine
           Routing Engine status:
           ...
           Idle 2 percent

the Idle value shows as low (2 % in the example above), and also the following command:

user@host> show system processes summary
  ...
  PID USERNAME PRI NICE SIZE RES STATE TIME WCPU COMMAND
  11639 root 52 0 283M 11296K select 12:15 44.97% eventd
  11803 root 81 0 719M 239M RUN 251:12 31.98% fxpc

the eventd and the fxpc processes might use higher WCPU percentage (respectively 44.97% and 31.98% in the above example).
 

This issue affects Juniper Networks Junos OS on EX2300 Series:

  • 18.1 versions prior to 18.1R3-S11;
  • 18.2 versions prior to 18.2R3-S5;
  • 18.3 versions prior to 18.3R2-S4, 18.3R3-S3;
  • 18.4 versions prior to 18.4R2-S5, 18.4R3-S4;
  • 19.1 versions prior to 19.1R3-S2;
  • 19.2 versions prior to 19.2R1-S5, 19.2R3;
  • 19.3 versions prior to 19.3R2-S4, 19.3R3;
  • 19.4 versions prior to 19.4R1-S3, 19.4R2-S1, 19.4R3;
  • 20.1 versions prior to 20.1R1-S2, 20.1R2.
     

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

This issue was seen during production usage.

This issue has been assigned CVE-2020-1668.

Solution:

The following software releases have been updated to resolve this specific issue: Junos OS 18.1R3-S11, 18.2R3-S5, 18.3R2-S4, 18.3R3-S3, 18.4R2-S5, 18.4R3-S4, 19.1R3-S2, 19.2R1-S5, 19.2R3, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2-S1, 19.4R3, 20.1R1-S2, 20.1R2, 20.2R1, and all subsequent releases.

This issue is being tracked as 1491905.

Workaround:

There are no available workarounds for this issue.

Implementation:
Software releases or updates are available for download at https://www.juniper.net/support/downloads/.
Modification History:
2020-10-14: Initial Publication.
CVSS Score:
6.5 (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
Severity Level:
Medium
Severity Assessment:
Information for how Juniper Networks uses CVSS can be found at KB 16446 "Common Vulnerability Scoring System (CVSS) and Juniper's Security Advisories."

Related Links

Comment on this article > Affected Products Browse the Knowledge Base for more articles related to these product categories. Select a category to begin.

Getting Up and Running with Junos

Getting Up and Running with Junos Security Alerts and Vulnerabilities Product Alerts and Software Release Notices Problem Report (PR) Search Tool EOL Notices and Bulletins JTAC User Guide Customer Care User Guide Pathfinder SRX High Availability Configurator SRX VPN Configurator Training Courses and Videos End User Licence Agreement Global Search