Product Affected

This issue affects Junos OS Evolved 19.4, 20.1, 20.2
Medium
6.5 (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

Problem

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@router:/var/log# ps aux | grep arpd
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 31418 49.1 1.0 *5813156* 351184 ? xxx /usr/sbin/arpd --app-name arpd -I object_select --shared-objects-mode 3


Memory usage can be monitored for the ndp process in a similar fashion:

user@router:/var/log# ps aux | grep ndp
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 14935 0.0 0.1 *5614052* 27256 ? Ssl Jun15 0:17 /usr/sbin/ndp -I no_tab_chk,object_select --app-name ndp --shared-obje
user@router:/var/log# ps aux | grep ndp
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 14935 0.0 0.1 *5725164* 27256 ? Ssl Jun15 0:17 /usr/sbin/ndp -I no_tab_chk,object_select --app-name ndp --shared-obje


This issue affects Juniper Networks Junos OS Evolved:

  • 19.4 versions prior to 19.4R2-S3-EVO;
  • 20.1 versions prior to 20.1R2-S4-EVO;
  • all versions of 20.2-EVO.

This issue does not affect Juniper Networks Junos OS Evolved versions prior to 19.4R2-EVO.

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

This issue was seen during production usage.

This issue has been assigned  CVE-2021-0292 .
 

Solution

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.

This issue is being tracked as  1531154 .
 

Software releases or updates are available for download at https://support.juniper.net/support/downloads/
 

Workaround

There are no known workarounds for this issue.
 

Severity Assessment

Information for how Juniper Networks uses CVSS can be found at KB 16446 [juniper.net] "Common Vulnerability Scoring System (CVSS) and Juniper's Security Advisories."

Modification History

2021-07-14: Initial Publication.

Related Information