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

published 2020-10-16 6y ago modified 2026-06-17 4mo ago also EUVD-2020-12528

cvss: 6.6; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 26%
public exploits: 0; none known

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.

Patch / fix

fixed in 1

Juniper Networks Junos OS Evolved 20.2R1-EVO

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Exploit prediction

0.33% chance of exploitation in the next 30 days, higher than 26% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	6.6	CVSS:3.1/AV:P/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD	2.0	7.2	AV:L/AC:L/Au:N/C:C/I:C/A:C

Affected products

Juniper Networks Junos OS Evolved

Classification

Weakness

CWE-284 Improper Access Control
CWE-613 DEPRECATED: Insufficient Session Expiration

References

kb.juniper.net /JSA11063
vendor-advisory

Sources

CVE List CVE-2020-1666
NVD CVE-2020-1666

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