When an MX Series Broadband Remote Access Server (BRAS) is configured as a Broadband Network Gateway (BNG) with DHCPv6 enabled, jdhcpd might crash when receiving a specific crafted DHCP response message on a subscriber interface. The daemon automatically restarts without intervention, but continuous receipt of specific crafted DHCP messages will repeatedly crash jdhcpd, leading to an extended Denial of Service (DoS) condition.

This issue only affects systems configured with DHCPv6 enabled.

DHCPv4 is unaffected by this issue.

This issue affects Juniper Networks Junos OS:

• 15.1 versions prior to 15.1R7-S5 on MX Series;
• 16.1 versions prior to 16.1R7-S5 on MX Series;
• 16.2 versions prior to 16.2R2-S10 on MX Series;
• 17.1 versions prior to 17.1R3-S1 on MX Series;
• 17.2 versions prior to 17.2R3-S2 on MX Series;
• 17.3 versions prior to 17.3R3-S6 on MX Series;
• 17.4 versions prior to 17.4R2-S5, 17.4R3 on MX Series;
• 18.1 versions prior to 18.1R3-S6 on MX Series;
• 18.2 versions prior to 18.2R2-S4, 18.2R3 on MX Series;
• 18.2X75 versions prior to 18.2X75-D50 on MX Series;
• 18.3 versions prior to 18.3R1-S5, 18.3R3 on MX Series;
• 18.4 versions prior to 18.4R2 on MX Series;
• 19.1 versions prior to 19.1R1-S2, 19.1R2 on MX Series.

Systems with DHCPv6 enabled will include a configuration similar to:

...

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-2019-0063 .
 

The following software releases have been updated to resolve this specific issue: 15.1R7-S5, 16.1R7-S5, 16.2R2-S10, 17.1R3-S1, 17.2R3-S2, 17.3R3-S6, 17.4R2-S5, 17.4R3, 18.1R3-S6, 18.2R2-S4, 18.2R3, 18.2X75-D50, 18.3R1-S5, 18.3R3, 18.4R2, 19.1R1-S2, 19.1R2, 19.2R1, and all subsequent releases.

This issue is being tracked as PR  1415242  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/ .
 

There are no viable workarounds for this issue.
 

• 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-2019-0063 at cve.mitre.org