CVE-2023-28966: Junos OS Evolved: Local low-privileged user with shell access can execute CLI commands as root

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-04-17 · updated 2026-06-17
Weakness: CWE-276

Description

An Incorrect Default Permissions vulnerability in Juniper Networks Junos OS Evolved allows a low-privileged local attacker with shell access to modify existing files or execute commands as root. The issue is caused by improper file and directory permissions on certain system files, allowing an attacker with access to these files and folders to inject CLI commands as root. This issue affects Juniper Networks Junos OS Evolved: All versions prior to 20.4R3-S5-EVO; 21.2 versions prior to 21.2R3-EVO; 21.3 versions prior to 21.3R2-EVO.

Affected products

Juniper Networks Junos OS Evolved: before 20.4; 20.4, 20.4-r1, 20.4-r1-s1, 20.4-r1-s2, 20.4-r2, 20.4-r2-s1 (+17) — fixed in 20.4

How to fix

Upgrade to a fixed version: Juniper Networks Junos OS Evolved 20.4. Check the vendor advisory for mitigations.

References

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