CVE-2021-0203

Junos OS: EX and QFX5K Series: Storm Control does not work as expected when Redundant Trunk Group is configured

Description

On Juniper Networks EX and QFX5K Series platforms configured with Redundant Trunk Group (RTG), Storm Control profile applied on the RTG interface might not take affect when it reaches the threshold condition. Storm Control enables the device to monitor traffic levels and to drop broadcast, multicast, and unknown unicast packets when a specified traffic level is exceeded, thus preventing packets from proliferating and degrading the LAN. Note: this issue does not affect EX2200, EX3300, EX4200, and EX9200 Series. This issue affects Juniper Networks Junos OS on EX Series and QFX5K Series: 15.1 versions prior to 15.1R7-S7; 16.1 versions prior to 16.1R7-S8; 17.2 versions prior to 17.2R3-S4; 17.3 versions prior to 17.3R3-S8; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2; 18.1 versions prior to 18.1R3-S10; 18.2 versions prior to 18.2R3-S5; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2; 18.4 versions prior to 18.4R2-S5, 18.4R3-S3; 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-S2, 20.1R2.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 15.1R7-S7, 16.1R7-S8, 17.2R3-S4, 17.3R3-S8, 17.4R2-S11, 17.4R3-S2, 18.1R3-S10, 18.2R3-S5, 18.3R2-S4, 18.3R3-S2, 18.4R2-S5, 18.4R3-S3, 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-S2, 20.1R2, 20.2R1 and all subsequent releases.

Workaround:

  • There are no known workarounds for this issue.

Category

8.6
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.39%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11093 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-0203?
CVE-2021-0203 has been scored as a high severity vulnerability.
How to fix CVE-2021-0203?
To fix CVE-2021-0203: The following software releases have been updated to resolve this specific issue: 15.1R7-S7, 16.1R7-S8, 17.2R3-S4, 17.3R3-S8, 17.4R2-S11, 17.4R3-S2, 18.1R3-S10, 18.2R3-S5, 18.3R2-S4, 18.3R3-S2, 18.4R2-S5, 18.4R3-S3, 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-S2, 20.1R2, 20.2R1 and all subsequent releases.
Is CVE-2021-0203 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-0203 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-2021-0203?
CVE-2021-0203 affects Juniper Networks Junos OS.
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