CVE-2020-1667

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

Description

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.

Remediation

Solution:

  • 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.

Workaround:

  • There are no viable workarounds for this issue.

Category

8.3
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.49%
Vendor Advisory juniper.net Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2020-1667?
CVE-2020-1667 has been scored as a high severity vulnerability.
How to fix CVE-2020-1667?
To fix CVE-2020-1667: 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.
Is CVE-2020-1667 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-1667 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-1667?
CVE-2020-1667 affects Juniper Networks Junos OS, Juniper Networks Junos OS.
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