An Out-of-bounds Read vulnerability in the flow processing daemon (flowd) of Juniper Networks Junos OS on SRX Series allows a local, authenticated attacker with low privileges, to cause a Denial of Service (DoS).

If a low privileged user executes a specific CLI command, flowd which is responsible for traffic forwarding in SRX crashes and generates a core dump. This will cause temporary traffic interruption until the flowd process is restarted automatically. Continued execution of this command will lead to a sustained DoS.
 

This issue affects Juniper Networks Junos OS on SRX Series:

• All versions prior to 20.2R3-S7;
• 20.3 version 20.3R1 and later versions;
• 20.4 versions prior to 20.4R3-S6;
• 21.1 versions prior to 21.1R3-S5;
• 21.2 versions prior to 21.2R3-S4;
• 21.3 versions prior to 21.3R3-S4;
• 21.4 versions prior to 21.4R3-S3;
• 22.1 versions prior to 22.1R3-S1;
• 22.2 versions prior to 22.2R3;
• 22.3 versions prior to 22.3R2;
• 22.4 versions prior to 22.4R1-S1, 22.4R2.

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-2023-36838.

The following software releases have been updated to resolve this specific issue: 20.2R3-S7, 20.4R3-S6, 21.1R3-S5, 21.2R3-S4, 21.3R3-S4, 21.4R3-S3, 22.1R3-S1, 22.2R3, 22.3R2, 22.4R1-S1, 22.4R2, 23.1R1, and all subsequent releases.

This issue is being tracked as 1691594

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

2023-07-12: 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-2023-36838 at www.cve.org