A vulnerability in Juniper Networks Junos OS, which only affects the release 18.4R2-S5, where a function is inconsistently implemented on Juniper Networks Junos QFX5000 Series and EX4600 Series, and if ' storm-control enhanced ' is configured,  can lead to the enhanced storm control filter group not be installed.  It will cause storm control not to work hence allowing an attacker to cause high CPU usage or packet loss issues by sending a large amount of broadcast or unknown unicast packets arriving the device.

This issue affects Juniper Networks QFX5100, QFX5110, QFX5120, QFX5200, QFX5210, EX4600, and EX4650, and QFX5100 with QFX 5e Series image installed.

QFX5130 and QFX5220 are not affected from this issue.

This issue only affects the above devices if configured with:

[ forwarding-options storm-control enhanced ]

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-2021-0294 .
 

The following software releases has been updated to resolve this specific issue: Junos OS 18.4R2-S6.

This issue is being tracked as  1544160 .
 

Software releases or updates are available for download at https://support.juniper.net/support/downloads/
 

There are no viable workarounds for this issue.
 

2021-07-14: Initial Publication.

• KB16613: Overview of the Juniper Networks SIRT Quarterly Security Bulletin Publication Process [juniper.net]
• KB16765: In which releases are vulnerabilities fixed? [juniper.net]
• KB16446: Common Vulnerability Scoring System (CVSS) and Juniper's Security Advisories [juniper.net]
• Report a Vulnerability - How to Contact the Juniper Networks Security Incident Response Team
• CVE-2021-0294: Enhanced storm control might not work leading to partial Denial of Service