CVE-2021-0292

Junos OS Evolved: Memory leak in arpd or ndp processes can lead to Denial of Service (DoS)

Description

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.

Remediation

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.

Workaround:

  • There are no known workarounds for this issue.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.08%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS Evolved
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11194 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-0292?
CVE-2021-0292 has been scored as a medium severity vulnerability.
How to fix CVE-2021-0292?
To fix CVE-2021-0292: 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.
Is CVE-2021-0292 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-0292 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-0292?
CVE-2021-0292 affects Juniper Networks Junos OS Evolved.
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