Vulnerability in Juniper Junos

CVE-2020-1667

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.

Vulnerability class: Race Condition

EPSS: 0.007 (49.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2020-1667?
CVE-2020-1667 is a high-severity vulnerability in Juniper Junos, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 8.3/10. Published 2020-10-16.
How severe is CVE-2020-1667?
High severity. CVSS v3 base score is 8.3 out of 10.
Is CVE-2020-1667 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.