high
8.8
CWE
326
Advisory Published
Updated

CVE-2018-0021: Junos OS: Short MacSec keys may allow man-in-the-middle attacks.

First published: Wed Apr 11 2018(Updated: )

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.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Juniper Junos=15.1x49
Juniper Junos=15.1x49-d10
Juniper Junos=15.1x49-d20
Juniper Junos=15.1x49-d30
Juniper Junos=15.1x49-d35
Juniper Junos=15.1x49-d40
Juniper Junos=15.1x49-d45
Juniper Junos=15.1x49-d50
Juniper Junos=15.1x49-d55
Juniper Junos=15.1x49-d60
Juniper Junos=15.1x49-d65
Juniper Junos=15.1x49-d70
Juniper Junos=15.1x49-d75
Juniper Junos=15.1x49-d80
Juniper Junos=15.1x49-d90
Juniper Junos=14.1
Juniper Junos=14.1-r1
Juniper Junos=14.1-r2
Juniper Junos=14.1-r3
Juniper Junos=14.1-r4
Juniper Junos=14.1-r5
Juniper Junos=14.1-r6
Juniper Junos=14.1-r7
Juniper Junos=14.1-r9
Juniper Junos=14.1x53
Juniper Junos=14.1x53-d10
Juniper Junos=14.1x53-d15
Juniper Junos=14.1x53-d16
Juniper Junos=14.1x53-d25
Juniper Junos=14.1x53-d26
Juniper Junos=14.1x53-d27
Juniper Junos=14.1x53-d30
Juniper Junos=14.1x53-d35
Juniper Junos=14.1x53-d40
Juniper Junos=14.1x53-d45
Juniper Junos=15.1x53
Juniper Junos=15.1x53-d10
Juniper Junos=15.1x53-d20
Juniper Junos=15.1x53-d21
Juniper Junos=15.1x53-d30
Juniper Junos=15.1x53-d32
Juniper Junos=15.1x53-d33
Juniper Junos=15.1x53-d34
Juniper Junos=15.1x53-d50
Juniper Junos=15.1x53-d51
Juniper Junos=15.1x53-d52
Juniper Junos=15.1x53-d55
Juniper Junos=15.1x53-d57
Juniper Junos=15.1x53-d58
Juniper Junos=16.1-r1
Juniper Junos=16.1-r2
Juniper Junos=16.1-r3
Juniper Junos=16.1-r4
Juniper Junos=16.2-r1
Juniper Junos=17.1-r1
Juniper Junos=15.1
Juniper Junos=15.1-r1
Juniper Junos=15.1-r2
Juniper Junos=15.1-r3
Juniper Junos=15.1-r4
Juniper Junos=15.1-r6

Remedy

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.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2018-0021?

    CVE-2018-0021 has been assessed with a high severity level due to the potential for unauthorized access and network vulnerabilities in affected Juniper devices.

  • How do I fix CVE-2018-0021?

    To fix CVE-2018-0021, ensure that all digits of the connectivity association name (CKN) and connectivity association key (CAK) are configured correctly as per the guidance in the product documentation.

  • Which systems are affected by CVE-2018-0021?

    CVE-2018-0021 affects various versions of Juniper JUNOS including 14.1, 15.1, and 16.1 across multiple revisions.

  • What is the impact of CVE-2018-0021 on my network?

    The impact of CVE-2018-0021 on your network could include increased risk of unauthorized access if the connectivity keys are improperly configured.

  • Are there any workarounds for CVE-2018-0021?

    Currently, the recommended workaround for CVE-2018-0021 is to manually configure the CKN and CAK with the appropriate length to prevent automatic zero configuration.

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