CVE-2020-1633

Summary

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

VendorProductVersion RangeStatus
Juniper NetworksJunos OS17.4 < 17.4R2-S9, 17.4R3affected
Juniper NetworksJunos OS18.1 < 18.1R3-S9affected
Juniper NetworksJunos OS18.2 < 18.2R2-S7, 18.2R3-S3affected
Juniper NetworksJunos OS18.2X75 < 18.2X75-D33, 18.2X75-D411, 18.2X75-D420, 18.2X75-D60affected
Juniper NetworksJunos OS18.3 < 18.3R1-S7, 18.3R2-S3, 18.3R3affected
Juniper NetworksJunos OS18.4 < 18.4R1-S5, 18.4R2-S2, 18.4R3affected
Juniper NetworksJunos OS19.1 < 19.1R1-S4, 19.1R2affected
Juniper NetworksJunos OS19.2 < 19.2R1-S3, 19.2R2affected

Weaknesses

  • CWE-20: CWE-20 Improper Input Validation

Workarounds

Configure 'no-arp-suppression' to disable Proxy ARP/NDP feature. For example:

[routing-instances <name> protocols evpn]

set no-arp-suppression

ADP Enrichment

CVE Program Container

Additional References

References