CVE-2020-1665

Junos OS: MX series/EX9200 Series: IPv6 DDoS protection does not work as expected.

Description

On Juniper Networks MX Series and EX9200 Series, in a certain condition the IPv6 Distributed Denial of Service (DDoS) protection might not take affect when it reaches the threshold condition. The DDoS protection allows the device to continue to function while it is under DDoS attack, protecting both the Routing Engine (RE) and the Flexible PIC Concentrator (FPC) during the DDoS attack. When this issue occurs, the RE and/or the FPC can become overwhelmed, which could disrupt network protocol operations and/or interrupt traffic. This issue does not affect IPv4 DDoS protection. This issue affects MX Series and EX9200 Series with Trio-based PFEs (Packet Forwarding Engines). Please refer to https://kb.juniper.net/KB25385 for the list of Trio-based PFEs. This issue affects Juniper Networks Junos OS on MX series and EX9200 Series: 17.2 versions prior to 17.2R3-S4; 17.2X75 versions prior to 17.2X75-D102, 17.2X75-D110; 17.3 versions prior to 17.3R3-S8; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2; 18.2 versions prior to 18.2R2-S7, 18.2R3, 18.2R3-S3; 18.2X75 versions prior to 18.2X75-D30; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 17.2R3-S4, 17.2X75-D102, 17.2X75-D110, 17.3R3-S8, 17.4R2-S11, 17.4R3-S2, 18.2R2-S7, 18.2R3, 18.2R3-S3, 18.2X75-D30, 18.3R2-S4, 18.3R3-S2, 18.4R1, and all subsequent releases.

Workaround:

  • There are no viable workarounds for this issue.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.23%
Vendor Advisory juniper.net Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11062 vendor advisory
https://kb.juniper.net/KB25385 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-1665?
CVE-2020-1665 has been scored as a medium severity vulnerability.
How to fix CVE-2020-1665?
To fix CVE-2020-1665: The following software releases have been updated to resolve this specific issue: Junos OS 17.2R3-S4, 17.2X75-D102, 17.2X75-D110, 17.3R3-S8, 17.4R2-S11, 17.4R3-S2, 18.2R2-S7, 18.2R3, 18.2R3-S3, 18.2X75-D30, 18.3R2-S4, 18.3R3-S2, 18.4R1, and all subsequent releases.
Is CVE-2020-1665 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-1665 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-1665?
CVE-2020-1665 affects Juniper Networks Junos OS.
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