A Use of an Uninitialized Resource vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows a local, authenticated attacker with low privileges to cause a Denial of Service (DoS).

On all Junos OS and Junos OS Evolved platforms, in a Multicast only Fast Reroute (MoFRR) scenario, the rpd process can crash when a a specific low privileged CLI command is executed. The rpd crash will impact all routing protocols until the process has automatically been restarted. As the operational state which makes this issue exploitable is outside the attackers control, this issue is considered difficult to exploit. Continued execution of this command will lead to a sustained DoS.

This issue affects:

Juniper Networks Junos OS

• 19.4 version 19.4R3-S5 and later versions prior to 19.4R3-S9;
• 20.1 version 20.1R2 and later versions;
• 20.2 versions prior to 20.2R3-S7;
• 20.3 versions prior to 20.3R3-S5;
• 20.4 versions prior to 20.4R3-S6;
• 21.1 versions prior to 21.1R3-S4;
• 21.2 versions prior to 21.2R3-S2;
• 21.3 versions prior to 21.3R3-S1;
• 21.4 versions prior to 21.4R3;
• 22.1 versions prior to 22.1R1-S2, 22.1R2;
• 22.2 versions prior to 22.2R2.

Juniper Networks Junos OS Evolved

• All versions prior to 20.4R3-S6-EVO;
• 21.1-EVO version 21.1R1-EVO and later versions;
• 21.2-EVO version 21.2R1-EVO and later versions;
• 21.3-EVO versions prior to 21.3R3-S1-EVO;
• 21.4-EVO versions prior to 21.4R3-EVO;
• 22.1-EVO versions prior to 22.1R1-S2-EVO, 22.1R2-EVO;
• 22.2-EVO versions prior to 22.2R2-EVO.

To be exposed to this issue an interface need to be configured as follows:

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-2023-36836.

The following software releases have been updated to resolve this specific issue:

Junos OS: 19.4R3-S9, 20.2R3-S7, 20.3R3-S5, 20.4R3-S6, 21.1R3-S4, 21.2R3-S2, 21.3R3-S1, 21.4R3, 22.1R1-S2, 22.1R2, 22.2R2, 22.3R1, and all subsequent releases;

Junos OS Evolved: 20.4R3-S6-EVO, 21.3R3-S1-EVO, 21.4R3-EVO, 22.1R1-S2-EVO, 22.1R2-EVO, 22.2R2-EVO, 22.3R1-EVO , and all subsequent releases.

This issue is being tracked as 1658458 and 1657491

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-2023-36836 at www.cve.org