CVE detail

CVE-2020-1633 — CVE-2020-1633

Published 2020-04-09 · Modified 2026-06-17 · Vendor juniper · Product junos · Source nvd
HIGH
severity
CVSS-derived band
7.4
CVSS v3
0–10 scale
0.0053
EPSS probability
exploitation probability, 30d
42.0%
EPSS percentile
percentile vs all CVEs
NOT LISTED
CISA KEV
known exploited catalog

Description

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 t

Remediation

vendor remediation guidance

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.

workarounds

Configure 'no-arp-suppression' to disable Proxy ARP/NDP feature. For example: [routing-instances <name> protocols evpn] # set no-arp-suppression

ProductVulnerable rangeFixed versionAdvisory
Juniper Networks Junos OS>=17.4<17.4R2-S9, 17.4R317.4R2-S9, 17.4R3advisory ↗
Juniper Networks Junos OS>=18.1<18.1R3-S918.1R3-S9advisory ↗
Juniper Networks Junos OS>=18.2<18.2R2-S7, 18.2R3-S318.2R2-S7, 18.2R3-S3advisory ↗
Juniper Networks Junos OS>=18.2X75<18.2X75-D33, 18.2X75-D411, 18.2X75-D420, 18.2X75-D6018.2X75-D33, 18.2X75-D411, 18.2X75-D420, 18.2X75-D60advisory ↗
Juniper Networks Junos OS>=18.3<18.3R1-S7, 18.3R2-S3, 18.3R318.3R1-S7, 18.3R2-S3, 18.3R3advisory ↗
Juniper Networks Junos OS>=18.4<18.4R1-S5, 18.4R2-S2, 18.4R318.4R1-S5, 18.4R2-S2, 18.4R3advisory ↗
Juniper Networks Junos OS>=19.1<19.1R1-S4, 19.1R219.1R1-S4, 19.1R2advisory ↗
Juniper Networks Junos OS>=19.2<19.2R1-S3, 19.2R219.2R1-S3, 19.2R2advisory ↗

References

cvedb.io · NVD · CISA KEV · FIRST EPSS · vendor advisories (CVE Program List v5). Informational only, no warranty — verify every remediation against the vendor advisory before acting on it. This product uses data from the NVD API but is not endorsed or certified by the NVD, CISA, FIRST.org or any vendor named. CVE® is a registered trademark of The MITRE Corporation.