CVE-2020-1633: Junos OS: MX Series: Crafted packets traversing a Broadband Network Gateway (BNG) configured with IPv6 NDP proxy could lead to Denial of Service

Published Apr 9, 2020
·
Updated

Due to a new NDP proxy feature for EVPN leaf nodes introduced in Junos OS 17.4, crafted NDPv6 packets could transit a Junos device configured as a Broadband Network Gateway (BNG) and reach the EVPN leaf node, causing a stale MAC address entry. This could cause legitimate traffic to be discarded, leading to a Denial of Service (DoS) condition. This issue only affects Junos OS 17.4 and later releases. Prior releases do not support this feature and are unaffected by this vulnerability. This issue only affects IPv6. IPv4 ARP proxy is unaffected by this vulnerability. This issue affects Juniper Networks Junos OS: 17.4 versions prior to 17.4R2-S9, 17.4R3 on MX Series; 18.1 versions prior to 18.1R3-S9 on MX Series; 18.2 versions prior to 18.2R2-S7, 18.2R3-S3 on MX Series; 18.2X75 versions prior to 18.2X75-D33, 18.2X75-D411, 18.2X75-D420, 18.2X75-D60 on MX Series; 18.3 versions prior to 18.3R1-S7, 18.3R2-S3, 18.3R3 on MX Series; 18.4 versions prior to 18.4R1-S5, 18.4R2-S2, 18.4R3 on MX Series; 19.1 versions prior to 19.1R1-S4, 19.1R2 on MX Series; 19.2 versions prior to 19.2R1-S3, 19.2R2 on MX Series.

Affected Software

180 affected components
Juniper Junos=17.4
Juniper Junos=17.4-r1
Juniper Junos=17.4-r1-s1
Juniper Junos=17.4-r1-s2
Juniper Junos=17.4-r1-s4
Juniper Junos=17.4-r1-s5
Juniper Junos=17.4-r1-s6
Juniper Junos=17.4-r1-s7
Juniper Junos=17.4-r2
Juniper Junos=17.4-r2-s1
Juniper Junos=17.4-r2-s2
Juniper Junos=17.4-r2-s3
Juniper Junos=17.4-r2-s4
Juniper Junos=17.4-r2-s5
Juniper Junos=17.4-r2-s6
Juniper Junos=17.4-r2-s7
Juniper Junos=17.4-r2-s8
Juniper Junos=18.1
Juniper Junos=18.1-r2
Juniper Junos=18.1-r2-s1
Juniper Junos=18.1-r2-s2
Juniper Junos=18.1-r2-s4
Juniper Junos=18.1-r3
Juniper Junos=18.1-r3-s1
Juniper Junos=18.1-r3-s2
Juniper Junos=18.1-r3-s3
Juniper Junos=18.1-r3-s4
Juniper Junos=18.1-r3-s6
Juniper Junos=18.1-r3-s7
Juniper Junos=18.1-r3-s8
Juniper Junos=18.2
Juniper Junos=18.2-r1
Juniper Junos=18.2-r1-s3
Juniper Junos=18.2-r1-s5
Juniper Junos=18.2-r2-s1
Juniper Junos=18.2-r2-s2
Juniper Junos=18.2-r2-s3
Juniper Junos=18.2-r2-s4
Juniper Junos=18.2-r2-s5
Juniper Junos=18.2-r2-s6
Juniper Junos=18.2-r3
Juniper Junos=18.2-r3-s1
Juniper Junos=18.2-r3-s2
Juniper Junos=18.2x75
Juniper Junos=18.2x75
Juniper Junos=18.2x75-d20
Juniper Junos=18.2x75-d30
Juniper Junos=18.3
Juniper Junos=18.3-r1
Juniper Junos=18.3-r1-s1
Juniper Junos=18.3-r1-s2
Juniper Junos=18.3-r1-s3
Juniper Junos=18.3-r1-s4
Juniper Junos=18.3-r1-s5
Juniper Junos=18.3-r1-s6
Juniper Junos=18.3-r2
Juniper Junos=18.3-r2-s1
Juniper Junos=18.3-r2-s2
Juniper Junos=18.4
Juniper Junos=18.4-r1
Juniper Junos=18.4-r1-s1
Juniper Junos=18.4-r1-s2
Juniper Junos=18.4-r1-s3
Juniper Junos=18.4-r1-s4
Juniper Junos=18.4-r2
Juniper Junos=18.4-r2-s1
Juniper Junos=19.1
Juniper Junos=19.1-r1
Juniper Junos=19.1-r1-s1
Juniper Junos=19.1-r1-s2
Juniper Junos=19.1-r1-s3
Juniper Junos=19.2
Juniper Junos=19.2-r1
Juniper Junos=19.2-r1-s1
Juniper Junos=19.2-r1-s2
Juniper MX10
Juniper Mx10000
Juniper MX10003
Juniper MX104
Juniper MX150
Juniper MX2008
Juniper MX2010
Juniper MX2020
Juniper MX204
Juniper MX240
Juniper Mx40
Juniper MX480
Juniper Mx5
Juniper Mx80
Juniper MX960
All of the following
Any of the following
Juniper Junos=17.4
Juniper Junos=17.4-r1
Juniper Junos=17.4-r1-s1
Juniper Junos=17.4-r1-s2
Juniper Junos=17.4-r1-s4
Juniper Junos=17.4-r1-s5
Juniper Junos=17.4-r1-s6
Juniper Junos=17.4-r1-s7
Juniper Junos=17.4-r2
Juniper Junos=17.4-r2-s1
Juniper Junos=17.4-r2-s2
Juniper Junos=17.4-r2-s3
Juniper Junos=17.4-r2-s4
Juniper Junos=17.4-r2-s5
Juniper Junos=17.4-r2-s6
Juniper Junos=17.4-r2-s7
Juniper Junos=17.4-r2-s8
Juniper Junos=18.1
Juniper Junos=18.1-r2
Juniper Junos=18.1-r2-s1
Juniper Junos=18.1-r2-s2
Juniper Junos=18.1-r2-s4
Juniper Junos=18.1-r3
Juniper Junos=18.1-r3-s1
Juniper Junos=18.1-r3-s2
Juniper Junos=18.1-r3-s3
Juniper Junos=18.1-r3-s4
Juniper Junos=18.1-r3-s6
Juniper Junos=18.1-r3-s7
Juniper Junos=18.1-r3-s8
Juniper Junos=18.2
Juniper Junos=18.2-r1
Juniper Junos=18.2-r1-s3
Juniper Junos=18.2-r1-s5
Juniper Junos=18.2-r2-s1
Juniper Junos=18.2-r2-s2
Juniper Junos=18.2-r2-s3
Juniper Junos=18.2-r2-s4
Juniper Junos=18.2-r2-s5
Juniper Junos=18.2-r2-s6
Juniper Junos=18.2-r3
Juniper Junos=18.2-r3-s1
Juniper Junos=18.2-r3-s2
Juniper Junos=18.2x75
Juniper Junos=18.2x75
Juniper Junos=18.2x75-d20
Juniper Junos=18.2x75-d30
Juniper Junos=18.3
Juniper Junos=18.3-r1
Juniper Junos=18.3-r1-s1
Juniper Junos=18.3-r1-s2
Juniper Junos=18.3-r1-s3
Juniper Junos=18.3-r1-s4
Juniper Junos=18.3-r1-s5
Juniper Junos=18.3-r1-s6
Juniper Junos=18.3-r2
Juniper Junos=18.3-r2-s1
Juniper Junos=18.3-r2-s2
Juniper Junos=18.4
Juniper Junos=18.4-r1
Juniper Junos=18.4-r1-s1
Juniper Junos=18.4-r1-s2
Juniper Junos=18.4-r1-s3
Juniper Junos=18.4-r1-s4
Juniper Junos=18.4-r2
Juniper Junos=18.4-r2-s1
Juniper Junos=19.1
Juniper Junos=19.1-r1
Juniper Junos=19.1-r1-s1
Juniper Junos=19.1-r1-s2
Juniper Junos=19.1-r1-s3
Juniper Junos=19.2
Juniper Junos=19.2-r1
Juniper Junos=19.2-r1-s1
Juniper Junos=19.2-r1-s2
Any of the following
Juniper MX10
Juniper Mx10000
Juniper MX10003
Juniper MX104
Juniper MX150
Juniper MX2008
Juniper MX2010
Juniper MX2020
Juniper MX204
Juniper MX240
Juniper Mx40
Juniper MX480
Juniper Mx5
Juniper Mx80
Juniper MX960

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 17.4R2-S9
  2. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 17.4R3
  3. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 18.1R3-S9
  4. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 18.2R2-S7
  5. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 18.2R3-S3
  6. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 18.2X75-D33
  7. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 18.2X75-D411
  8. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 18.2X75-D420
  9. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 18.2X75-D60
  10. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 18.3R1-S7
  11. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 18.3R2-S3
  12. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 18.3R3
  13. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 18.3R3-S1
  14. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 18.4R1-S5
  15. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 18.4R2-S2
  16. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 18.4R3
  17. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 19.1R1-S4
  18. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 19.1R2
  19. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 19.2R1-S3
  20. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 19.2R2
  21. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 19.3R1
  22. Upgrade

    Upgrade Junos OS (MX Series) to a version that resolves this vulnerability.

    Fixed in 19.4R1

Event History

Apr 9, 2020
CVE Published
via MITRE·11:09 PM
Data Sourced
via MITRE·11:09 PM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·11:15 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2020-1633?

The severity of CVE-2020-1633 is considered high due to the potential for legitimate traffic impact.

2

How do I fix CVE-2020-1633?

To fix CVE-2020-1633, you should update to the latest version of Junos OS that addresses this vulnerability.

3

Which versions of Junos OS are affected by CVE-2020-1633?

Junos OS versions 17.4, 18.1, 18.2, 18.3, 18.4, and 19.1 are affected by CVE-2020-1633.

4

What type of attack does CVE-2020-1633 involve?

CVE-2020-1633 involves an exploitation of crafted Neighbor Discovery Protocol for IPv6 (NDPv6) packets.

5

What can happen if CVE-2020-1633 is exploited?

Exploitation of CVE-2020-1633 can lead to stale MAC address entries, causing disruptions in network traffic.

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