CVE-2020-1687

Junos OS: EX4300-MP/EX4600/QFX5K Series: High CPU load due to receipt of specific layer 2 frames in EVPN-VXLAN deployment.

Description

On Juniper Networks EX4300-MP Series, EX4600 Series and QFX5K Series deployed in (Ethernet VPN) EVPN-(Virtual Extensible LAN) VXLAN configuration, receipt of a stream of specific VXLAN encapsulated layer 2 frames can cause high CPU load, which could lead to network protocol operation issue and traffic interruption. This issue affects devices that are configured as a Layer 2 or Layer 3 gateway of an EVPN-VXLAN deployment. The offending layer 2 frames that cause the issue originate from a different access switch that get encapsulated within the same EVPN-VXLAN domain. This issue affects Juniper Networks Junos OS on EX4300-MP Series, EX4600 Series and QFX5K Series: 17.3 versions prior to 17.3R3-S9; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2, 17.4R3-S3; 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 19.1R2-S2, 19.1R3-S2; 19.2 versions prior to 19.2R1-S5, 19.2R2-S1, 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-S3, 20.1R2.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 17.3R3-S9, 17.4R2-S11, 17.4R3-S2, 17.4R3-S3, 18.1R3-S11, 18.2R3-S5, 18.3R2-S4, 18.3R3-S3, 18.4R2-S5, 18.4R3-S4, 19.1R2-S2, 19.1R3-S2, 19.2R1-S5, 19.2R2-S1, 19.2R3, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2-S1, 19.4R3, 20.1R1-S3, 20.1R2, 20.2R1 and all subsequent releases.

Workaround:

  • There are no viable workarounds for this issue.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.08%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11084 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-1687?
CVE-2020-1687 has been scored as a medium severity vulnerability.
How to fix CVE-2020-1687?
To fix CVE-2020-1687: The following software releases have been updated to resolve this specific issue: Junos OS 17.3R3-S9, 17.4R2-S11, 17.4R3-S2, 17.4R3-S3, 18.1R3-S11, 18.2R3-S5, 18.3R2-S4, 18.3R3-S3, 18.4R2-S5, 18.4R3-S4, 19.1R2-S2, 19.1R3-S2, 19.2R1-S5, 19.2R2-S1, 19.2R3, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2-S1, 19.4R3, 20.1R1-S3, 20.1R2, 20.2R1 and all subsequent releases.
Is CVE-2020-1687 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-1687 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-2020-1687?
CVE-2020-1687 affects Juniper Networks Junos OS.
This platform uses data from the NIST NVD, MITRE CVE, MITRE CWE, First.org and CISA KEV but is not endorsed or certified by these entities. CVE is a registred trademark of the MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. CWE is a registred trademark of the MITRE Corporation and the authoritative source of CWE content is MITRE's CWE web site.
© 2025 Under My Watch. All Rights Reserved.