An Allocation of Resources Without Limits or Throttling vulnerability in Juniper Networks Junos OS allows an unauthenticated, network-based attacker to cause Denial of Service (DoS).

On all Junos OS QFX5000 Series and EX4000 Series platforms, when a high number of VLANs are configured, a specific DHCP packet will cause PFE hogging which will lead to dropping of socket connections.

This issue affects:

Juniper Networks Junos OS on QFX5000 Series and EX4000 Series

• 21.1 versions prior to 21.1R3-S5;
• 21.2 versions prior to 21.2R3-S5;
• 21.3 versions prior to 21.3R3-S5;
• 21.4 versions prior to 21.4R3-S4;
• 22.1 versions prior to 22.1R3-S3;
• 22.2 versions prior to 22.2R3-S1;
• 22.3 versions prior to 22.3R2-S2, 22.3R3;
• 22.4 versions prior to 22.4R2.

This issue does not affect Juniper Networks Junos OS versions prior to 21.1R1

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-2023-44191.

The following software releases have been updated to resolve this specific issue: Junos OS 21.2R3-S5, 21.3R3-S5, 21.4R3-S4, 22.1R3-S3, 22.2R3-S1, 22.3R2-S2, 22.3R3, 22.4R2, 23.2R1, and all subsequent releases.

This issue is being tracked as PR 1711644 which is visible on the Customer Support website.

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

2023-10-11: 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-2023-44191 at cve.mitre.org
• https://supportportal.juniper.net/JSA73155 [juniper.net]