CVE-2020-1666

Junos OS Evolved: 'console log-out-on-disconnect' fails to terminate session on console cable disconnection

Description

The system console configuration option 'log-out-on-disconnect' In Juniper Networks Junos OS Evolved fails to log out an active CLI session when the console cable is disconnected. This could allow a malicious attacker with physical access to the console the ability to resume a previous interactive session and possibly gain administrative privileges. This issue affects all Juniper Networks Junos OS Evolved versions after 18.4R1-EVO, prior to 20.2R1-EVO.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS Evolved 20.2R1-EVO and all subsequent releases.

Workaround:

  • Limit access to the physical console to only trusted system administrators.

Categories

6.6
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.04%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS Evolved
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11063 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-1666?
CVE-2020-1666 has been scored as a medium severity vulnerability.
How to fix CVE-2020-1666?
To fix CVE-2020-1666: The following software releases have been updated to resolve this specific issue: Junos OS Evolved 20.2R1-EVO and all subsequent releases.
Is CVE-2020-1666 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-1666 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-2020-1666?
CVE-2020-1666 affects Juniper Networks Junos OS Evolved.
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