CVE-2021-0292: juniper networks junos os evolved Uncontrolled Resource Consumption
Vulnerability summary
CVE-2021-0292 is a medium (CVSS 6.5) Uncontrolled Resource Consumption vulnerability in juniper networks junos os evolved. EPSS estimates a 0.38% chance of exploitation in the next 30 days, higher than 30.5% of scored vulnerabilities.
Timeline
- 15-07-2021PublishedVulnerability first disclosed.
- 16-09-2024Last modifiedVulnerability information updated.
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.
CVSS metrics
3 scores · 2 sources · 2 versions- NVDNIST6.5MediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.38%
Chance of exploitation in the next 30 days
Percentile
31%
Versus all other CVEs
30-day change
0.00 pp
From 0.38% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Juniper1 product
- junos_os_evolved19.4:r1 | 19.4:r2 | 19.4:r2-s1 | 19.4:r2-s2 | 20.1 | 20.1:r1 | 20.1:r1-s1 | 20.1:r2 | 20.1:r2-s1 | 20.1:r2-s2 | 20.1:r2-s3 | 20.2
Juniper networks1 product
- junos os evolved≥ 19.4, < 19.4R2-S3-EVO | ≥ 20.1, < 20.1R2-S4-EVO | ≥ 20.2R1-EVO, < 20.2*
2 vendors · 2 products