CVE-2020-1665
On Juniper Networks MX Series and EX9200 Series, in a certain condition the IPv6 Distributed Denial of Service (DDoS) protection might not take affect when it reaches the threshold condition. The DDoS protection allows the device to continue to function while it is under DDoS attack, protecting both the Routing Engine (RE) and the Flexible PIC Concentrator (FPC) during the DDoS attack. When this issue occurs, the RE and/or the FPC can become overwhelmed, which could disrupt network protocol operations and/or interrupt traffic. This issue does not affect IPv4 DDoS protection. This issue affects MX Series and EX9200 Series with Trio-based PFEs (Packet Forwarding Engines). Please refer to https://kb.juniper.net/KB25385 for the list of Trio-based PFEs. This issue affects Juniper Networks Junos OS on MX series and EX9200 Series: 17.2 versions prior to 17.2R3-S4; 17.2X75 versions prior to 17.2X75-D102, 17.2X75-D110; 17.3 versions prior to 17.3R3-S8; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2; 18.2 versions prior to 18.2R2-S7, 18.2R3, 18.2R3-S3; 18.2X75 versions prior to 18.2X75-D30; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2.
Scoring
- Severity
- MEDIUM
- CVSS base score
- 5.3
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- EPSS probability
- 0.23%
- CWE
- CWE-794
- Published
- 2020-10-16
- Last modified
- 2026-03-14
Affected products
- Juniper Networks Junos OS
- Juniper Networks Junos OS
- Juniper Networks Junos OS
- Juniper Networks Junos OS
- Juniper Networks Junos OS
- Juniper Networks Junos OS
- Juniper Networks Junos OS
Weakness type
Related vulnerabilities
- CVE-2026-21876 — OWASP CRS has multipart bypass using multiple content-type parts
- CVE-2021-0233 — Junos OS: ACX500 Series, ACX4000 Series: Denial of Service due to FFEB crash while processing high rate of specific packets.
- CVE-2021-0203 — Junos OS: EX and QFX5K Series: Storm Control does not work as expected when Redundant Trunk Group is configured
- CVE-2019-0002 — Junos OS: EX2300 and EX3400 series: Certain stateless firewall filter rules might not take effect