high
7.4
CWE
20
Advisory Published
Updated

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

First published: Thu Apr 09 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.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
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

Remedy

The following software releases have been updated to resolve this specific issue: 17.4R2-S9, 17.4R3, 18.1R3-S9, 18.2R2-S7, 18.2R3-S3, 18.2X75-D33, 18.2X75-D411, 18.2X75-D420, 18.2X75-D60, 18.3R1-S7, 18.3R2-S3, 18.3R3, 18.3R3-S1, 18.4R1-S5, 18.4R2-S2, 18.4R3, 19.1R1-S4, 19.1R2, 19.2R1-S3, 19.2R2, 19.3R1, 19.4R1, and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • 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.

  • 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.

  • 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.

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

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

  • 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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