An Uncontrolled Resource Consumption vulnerability in the ARP daemon (arpd) and Network Discovery Protocol (ndp) process of Juniper Networks Junos OS Evolved allows a malicious attacker on the local network to consume memory resources, ultimately resulting in a Denial of Service (DoS) condition. Link-layer functions such as IPv4 and/or IPv6 address resolution may be impacted, leading to traffic loss. The processes do not recover on their own and must be manually restarted. Changes in memory usage can be monitored using the following shell commands (header shown for clarity): user@router:/var/log# ps aux | grep arpd USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND root 31418 59.0 0.7 *5702564* 247952 ? xxx /usr/sbin/arpd --app-name arpd -I object_select --shared-objects-mode 3 user@ro
The following software releases have been updated to resolve this specific issue: Junos OS Evolved 19.4R2-S3-EVO, 20.1R2-S4-EVO, 20.3R1-EVO, and all subsequent releases.
There are no known workarounds for this issue.
| Product | Vulnerable range | Fixed version | Advisory |
|---|---|---|---|
| Juniper Networks Junos OS Evolved | >=19.4<19.4R2-S3-EVO | 19.4R2-S3-EVO | advisory ↗ |
| Juniper Networks Junos OS Evolved | >=20.1<20.1R2-S4-EVO | 20.1R2-S4-EVO | advisory ↗ |
| Juniper Networks Junos OS Evolved | >=20.2R1-EVO<20.2* | 20.2* | advisory ↗ |