CVE-2025-30661

/// Technical description

An Incorrect Permission Assignment for Critical Resource vulnerability in line card script processing of Juniper Networks Junos OS allows a local, low-privileged user to install scripts to be executed as root, leading to privilege escalation.

A local user with access to the local file system can copy a script to the router in a way that will be executed as root, as the system boots. Execution of the script as root can lead to privilege escalation, potentially providing the adversary complete control of the system.

This issue only affects specific line cards, such as the MPC10, MPC11, LC4800, LC9600, MX304-LMIC16, SRX4700, and EX9200-15C.

This issue affects Junos OS: * from 23.2 before 23.2R2-S4, 

* from 23.4 before 23.4R2-S5, 

* from 24.2 before 24.2R2-S1, 

* from 24.4 before 24.4R1-S3, 24.4R2.

This issue does not affect versions prior to 23.1R2.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References