When configuring a stateless firewall filter in Junos OS, terms named using the format "internal-n" (e.g. "internal-1", "internal-2", etc.) are silently ignored. No warning is issued during configuration, and the config is committed without error, but the filter criteria will match all packets leading to unexpected results.

Affected releases are Juniper Networks Junos OS:

• All versions prior to and including 12.3;
• 14.1X53 versions prior to 14.1X53-D130, 14.1X53-D49;
• 15.1 versions prior to 15.1F6-S12, 15.1R7-S4;
• 15.1X49 versions prior to 15.1X49-D161, 15.1X49-D170;
• 15.1X53 versions prior to 15.1X53-D236, 15.1X53-D496, 15.1X53-D69;
• 16.1 versions prior to 16.1R7-S4, 16.1R7-S5;
• 16.2 versions prior to 16.2R2-S9;
• 17.1 versions prior to 17.1R3;
• 17.2 versions prior to 17.2R1-S8, 17.2R3-S1;
• 17.3 versions prior to 17.3R3-S4;
• 17.4 versions prior to 17.4R1-S7, 17.4R2-S3;
• 18.1 versions prior to 18.1R2-S4, 18.1R3-S4;
• 18.2 versions prior to 18.2R1-S5, 18.2R2-S1;
• 18.2X75 versions prior to 18.2X75-D40;
• 18.3 versions prior to 18.3R1-S3;
• 18.4 versions prior to 18.4R1-S1, 18.4R1-S2.

Sample configuration:

term internal-1 {
  from {
    source-address {
      192.168.32.21/32;
    }
    destination-address {
      192.168.197.64/30;
    }
    protocol udp;
    destination-port 123;
  }
  then {
    count scan-ad-internal-1;
    accept;
  }
}

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-2019-0036 .
 

The following software releases have been updated to resolve this specific issue: Junos OS 14.1X53-D130, 14.1X53-D49, 15.1F6-S12, 15.1R7-S4, 15.1X49-D161, 15.1X49-D170, 15.1X53-D236, 15.1X53-D496, 15.1X53-D69, 16.1R7-S4, 16.2R2-S9, 17.1R3, 17.2R1-S8, 17.2R3-S1, 17.3R3-S4, 17.4R1-S7, 17.4R2-S3, 18.1R2-S4, 18.1R3-S4, 18.2R1-S5, 18.2R2-S1, 18.2X75-D40, 18.3R1-S3, 18.4R1-S1, 19.1R1, and all subsequent releases.

Note: Fixes are not available for Junos OS 12.1X46, 12.3X48, or 12.3R12 due to the high risk of making changes to earlier releases, and the easily implemented available workaround.

This issue is being tracked as PR  1394922  which is visible on the Customer Support website.

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

Software Releases, patches and updates are available at  https://www.juniper.net/support/downloads/ .
 

Avoid configuring firewall filter names of the format: internal-n
 

• 2019-04-10: Initial Publication
• 2019-04-10: Updated IP addresses in example

• 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