CVE-2018-0021

Junos OS: Short MacSec keys may allow man-in-the-middle attacks.

Description

If all 64 digits of the connectivity association name (CKN) key or all 32 digits of the connectivity association key (CAK) key are not configured, all remaining digits will be auto-configured to 0. Hence, Juniper devices configured with short MacSec keys are at risk to an increased likelihood that an attacker will discover the secret passphrases configured for these keys through dictionary-based and brute-force-based attacks using spoofed packets. Affected releases are Juniper Networks Junos OS: 14.1 versions prior to 14.1R10, 14.1R9; 14.1X53 versions prior to 14.1X53-D47; 15.1 versions prior to 15.1R4-S9, 15.1R6-S6, 15.1R7; 15.1X49 versions prior to 15.1X49-D100; 15.1X53 versions prior to 15.1X53-D59; 16.1 versions prior to 16.1R3-S8, 16.1R4-S8, 16.1R5; 16.2 versions prior to 16.2R1-S6, 16.2R2; 17.1 versions prior to 17.1R2.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 14.1R9, 14.1X53-D47, 15.1R4-S9, 15.1R6-S6, 15.1R7, 15.1X49-D100, 15.1X53-D59, 16.1R3-S8, 16.1R4-S8, 16.1R5, 16.2R1-S6, 16.2R2, 17.1R2, 17.2R1 and all subsequent releases.

Workaround:

  • Configure all 64 digits of a CKN. Configure all 32 digits of a CAK. See the junos task topic macsec for further information.
8.8
CVSS
Severity: High
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.17%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
http://www.securitytracker.com/id/1040789 vdb entry third party advisory
https://kb.juniper.net/JSA10854 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2018-0021?
CVE-2018-0021 has been scored as a high severity vulnerability.
How to fix CVE-2018-0021?
To fix CVE-2018-0021: The following software releases have been updated to resolve this specific issue: 14.1R9, 14.1X53-D47, 15.1R4-S9, 15.1R6-S6, 15.1R7, 15.1X49-D100, 15.1X53-D59, 16.1R3-S8, 16.1R4-S8, 16.1R5, 16.2R1-S6, 16.2R2, 17.1R2, 17.2R1 and all subsequent releases.
Is CVE-2018-0021 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2018-0021 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-2018-0021?
CVE-2018-0021 affects Juniper Networks Junos OS.
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