An Improper Validation of Array Index vulnerability in the SIP ALG of Juniper Networks Junos OS on SRX 5000 Series allows a network-based, unauthenticated attacker to cause a Denial of Service (DoS).
 

When an attacker sends an SIP packets with a malformed SDP field then the SIP ALG can not process it which will lead to an FPC crash and restart. Continued receipt of these specific packets will lead to a sustained Denial of Service.

This issue can only occur when both below mentioned conditions are fulfilled:

1. Call distribution needs to be enabled:

2. The SIP ALG needs to be enabled, either implicitly / by default or by way of configuration. To confirm whether SIP ALG is enabled on SRX, and MX with SPC3 use the following command:

This issue affects Juniper Networks Junos OS on SRX 5000 Series:

• 20.4 versions prior to 20.4R3-S5;
• 21.1 versions prior to 21.1R3-S4;
• 21.2 versions prior to 21.2R3-S3;
• 21.3 versions prior to 21.3R3-S3;
• 21.4 versions prior to 21.4R3-S2;
• 22.1 versions prior to 22.1R2-S2, 22.1R3;
• 22.2 versions prior to 22.2R3;
• 22.3 versions prior to 22.3R1-S1, 22.3R2.

This issue does not affect Juniper Networks Junos OS versions prior to 20.4R1.

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-2023-22408.

The following software releases have been updated to resolve this specific issue: 20.4R3-S5, 21.1R3-S4, 21.2R3-S3, 21.3R3-S3, 21.4R3-S2, 22.1R2-S2, 22.1R3, 22.2R3, 22.3R1-S1, 22.3R2, 22.4R1, and all subsequent releases.

This issue is being tracked as 1658604.

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-2023-22408 at cve.mitre.org