An Improper Check for Unusual or Exceptional Conditions in Juniper Networks Junos OS Evolved may cause the stateless firewall filter configuration which uses the action 'policer' in certain combinations with other options to not take effect.

An administrator can use the following CLI command to see the failures with filter configuration:

This issue affects Juniper Networks Junos OS Evolved:

• Versions 19.1R1-EVO and above prior to 20.3R1-S2-EVO, 20.3R2-EVO.

This issue does not affect Juniper Networks Junos OS.

The examples of the config stanza affected by this issue:

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-2021-0225 .

The following software releases have been updated to resolve this specific issue: Junos OS Evolved: 20.3R1-S2-EVO, 20.3R2-EVO, 20.4R1-EVO, and all subsequent releases.

This issue is being tracked as 1528091 .

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

There are no viable workarounds for this issue.

2021-04-14: 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 Security Vulnerability - How to Contact the Juniper Networks Security Incident Response Team
• CVE-2021-0225 at cve.mitre.org