CVE-2024-39520: Juniper Junos OS Evolved

High severity, CVSS 7.8. EPSS: 0.3% chance of exploitation in the next 30 days.

An Improper Neutralization of Special Elements vulnerability in Juniper Networks Junos OS Evolved commands allows a local, authenticated attacker with low privileges to escalate their privileges to 'root' leading to a full compromise of the system. The Junos OS Evolved CLI doesn't properly handle command options in some cases, allowing users which execute specific CLI commands with a crafted set of parameters to escalate their privileges to root on shell level. This issue affects Junos OS Evolved: * All version before 20.4R3-S6-EVO,  * 21.2-EVO versions before 21.2R3-S4-EVO, * 21.4-EVO versions before 21.4R3-S6-EVO,  * 22.2-EVO versions before 22.2R2-S1-EVO, 22.2R3-EVO,  * 22.3-EVO versions before 22.3R2-EVO.

Affected products

• Juniper Junos OS Evolved: before 20.4 (fixed in 20.4); version 20.4 only; version 21.2 only; version 21.4 only; version 22.2 only; version 22.3 only

Published 2024-07-11. Last modified 2026-06-17.