CVE-2020-1667: Junos OS: MX Series: Services card might restart due to a race condition when DNS filtering is enabled.

Published Oct 16, 2020

Updated

When DNS filtering is enabled on Juniper Networks Junos MX Series with one of the following cards MS-PIC, MS-MIC or MS-MPC, an incoming stream of packets processed by the Multiservices PIC Management Daemon (mspmand) process might be bypassed due to a race condition. Due to this vulnerability, mspmand process, responsible for managing "URL Filtering service", can crash, causing the Services PIC to restart. While the Services PIC is restarting, all PIC services including DNS filtering service (DNS sink holing) will be bypassed until the Services PIC completes its boot process. This issue affects Juniper Networks Junos OS: 17.3 versions prior to 17.3R3-S8; 18.3 versions prior to 18.3R3-S1; 18.4 versions prior to 18.4R3; 19.1 versions prior to 19.1R3; 19.2 versions prior to 19.2R2; 19.3 versions prior to 19.3R3. This issue does not affect Juniper Networks Junos OS 17.4, 18.1, and 18.2.

Affected Software

56 affected components

Juniper Junos=17.3

Juniper Junos=17.3-r1-s1

Juniper Junos=17.3-r2

Juniper Junos=17.3-r2-s1

Juniper Junos=17.3-r2-s2

Juniper Junos=17.3-r2-s3

Juniper Junos=17.3-r2-s4

Juniper Junos=17.3-r2-s5

Juniper Junos=17.3-r3

Juniper Junos=17.3-r3-s1

Juniper Junos=17.3-r3-s2

Juniper Junos=17.3-r3-s3

Juniper Junos=17.3-r3-s4

Juniper Junos=17.3-r3-s7

Juniper Junos=18.3

Juniper Junos=18.3-r1

Juniper Junos=18.3-r1-s1

Juniper Junos=18.3-r1-s2

Juniper Junos=18.3-r1-s3

Juniper Junos=18.3-r1-s5

Juniper Junos=18.3-r1-s6

Juniper Junos=18.3-r2

Juniper Junos=18.3-r2-s1

Juniper Junos=18.3-r2-s2

Juniper Junos=18.3-r2-s3

Juniper Junos=18.3-r3

Juniper Junos=18.4

Juniper Junos=18.4-r1

Juniper Junos=18.4-r1-s1

Juniper Junos=18.4-r1-s2

Juniper Junos=18.4-r1-s5

Juniper Junos=18.4-r1-s6

Juniper Junos=18.4-r2

Juniper Junos=18.4-r2-s1

Juniper Junos=18.4-r2-s2

Juniper Junos=18.4-r2-s3

Juniper Junos=18.4-r2-s4

Juniper Junos=19.1

Juniper Junos=19.1-r1

Juniper Junos=19.1-r1-s1

Juniper Junos=19.1-r1-s2

Juniper Junos=19.1-r1-s3

Juniper Junos=19.1-r1-s4

Juniper Junos=19.1-r2

Juniper Junos=19.1-r2-s1

Juniper Junos=19.2

Juniper Junos=19.2-r1

Juniper Junos=19.2-r1-s1

Juniper Junos=19.2-r1-s2

Juniper Junos=19.2-r1-s3

Juniper Junos=19.3

Juniper Junos=19.3-r1

Juniper Junos=19.3-r1-s1

Juniper Junos=19.3-r2

Juniper Junos=19.3-r2-s1

Juniper Junos=19.3-r2-s2

Remediation

Information

The following software releases have been updated to resolve this specific issue: Junos OS 17.3R3-S8, 18.3R3-S1, 18.4R3, 19.1R3, 19.2R2, 19.3R3, 19.4R1, and all subsequent releases.

Event History

Oct 16, 2020

CVE Published

via MITRE·08:31 PM

Data Sourced

via MITRE·08:31 PM

RemedyDescriptionSeverityWeakness

Frequently Asked Questions

What is the severity of CVE-2020-1667?

CVE-2020-1667 has been rated as high severity due to its potential to bypass incoming packet filtering.

How do I fix CVE-2020-1667?

To mitigate CVE-2020-1667, users should upgrade to the latest patched version of Junos OS as recommended by Juniper Networks.

Which devices are affected by CVE-2020-1667?

CVE-2020-1667 affects Juniper Networks Junos MX Series devices configured with DNS filtering enabled and specific cards like MS-PIC, MS-MIC, or MS-MPC.

What is the cause of CVE-2020-1667?

CVE-2020-1667 is caused by a race condition occurring in the Multiservices PIC Management Daemon (mspmand) process.

What should I do if I can't immediately update for CVE-2020-1667?

If an immediate update for CVE-2020-1667 isn't possible, consider disabling DNS filtering as a temporary measure until the update can be applied.