An Improper Preservation of Consistency Between Independent Representations of Shared State vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows an adjacent, unauthenticated attacker to cause a Denial of Service (DoS) to device due to out of resources.
 

When a device is configured with "service-provider/SP style" switching, and mac-limiting is configured on an Aggregated Ethernet (ae) interface, and then a PFE is restarted or the device is rebooted, mac-limiting doesn't work anymore. Please note that the issue might not be apparent as traffic will continue to flow through the device although the mac table and respective logs will indicate that mac limit is reached.

Functionality can be restored by removing and re-adding the MAC limit configuration.
 

This issue affects Juniper Networks Junos OS on QFX5k Series, EX46xx Series:

• All versions prior to 20.2R3-S5;
• 20.3 versions prior to 20.3R3-S5;
• 20.4 versions prior to 20.4R3-S4;
• 21.1 versions prior to 21.1R3-S3;
• 21.2 versions prior to 21.2R3-S1;
• 21.3 versions prior to 21.3R3 on;
• 21.4 versions prior to 21.4R3 on;
• 22.1 versions prior to 22.1R2 on.

To be vulnerable to this issue a "service provider/SP"-style configuration like the following needs to be present:

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-2023-22405.

The following software releases have been updated to resolve this specific issue: 20.2R3-S5, 20.3R3-S5, 20.4R3-S4, 21.1R3-S3, 21.2R3-S1, 21.3R3, 21.4R3, 22.1R2, 22.2R1, and all subsequent releases.
 

This issue is being tracked as 1659873.
 

Note: Juniper SIRT's policy is not to evaluate releases which are beyond End of Engineering (EOE) or End of Life (EOL).

• 2023-01-11: 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-2023-22405 at cve.mitre.org