A command injection vulnerability in install package validation subsystem of Juniper Networks Junos OS that may allow a locally authenticated attacker with privileges to execute commands with root privilege. To validate a package in Junos before installation, an administrator executes the command ' request system software add validate-on-host ' via the CLI. An attacker with access to this CLI command may be able to exploit this vulnerability.

This issue affects Juniper Networks Junos OS:

• all versions prior to 17.3R3-S10;
• 17.4 versions prior to 17.4R2-S12, 17.4R3-S3;
• 18.1 versions prior to 18.1R3-S11;
• 18.2 versions prior to 18.2R2-S8, 18.2R3-S6;
• 18.3 versions prior to 18.3R3-S4;
• 18.4 versions prior to 18.4R1-S8, 18.4R2-S7, 18.4R3-S6;
• 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3-S3;
• 19.2 versions prior to 19.2R3-S1;
• 19.3 versions prior to 19.3R2-S5, 19.3R3-S1;
• 19.4 versions prior to 19.4R2-S2, 19.4R3-S1;
• 20.1 versions prior to 20.1R2;
• 20.2 versions prior to 20.2R1-S2, 20.2R2;
• 20.3 versions prior to 20.3R1-S1, 20.3R2.

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

This issue was discovered during external security research.

This issue has been assigned  CVE-2021-0219 .
 

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

Junos OS: 17.3R3-S10, 17.4R2-S12, 17.4R3-S3, 18.1R3-S11, 18.2R2-S8, 18.2R3-S6, 18.2X75-D34, 18.3R3-S4, 18.4R1-S8, 18.4R2-S7, 18.4R3-S6, 19.1R1-S6, 19.1R2-S2, 19.1R3-S3, 19.2R3-S1, 19.3R2-S5, 19.3R3-S1, 19.4R2-S2, 19.4R3-S1, 20.1R2, 20.2R1-S2, 20.2R2, 20.3R1-S1, 20.3R2, 20.4R1, and all subsequent releases.

This issue is being tracked as  1519337 .
 

Software releases or updates are available for download at https://www.juniper.net/support/downloads/ .
 

Use access lists or firewall filters to limit CLI access to the device only from trusted, administrative networks or hosts.

Limit access to the Junos OS CLI to only trusted system administrators.

Restrict access to the ' request system software add validate-on-host ' command.
 

2021-01-13: 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-2021-0219 at cve.mitre.org

Juniper SIRT would like to acknowledge and thank Hoàng Thạch Nguyễn (d4rkn3ss) of STAR Labs for responsibly reporting this vulnerability.