CVE-2025-30661

NVD	https://nvd.nist.gov/vuln/detail/CVE-2025-30661
CWE	https://cwe.mitre.org/data/definitions/732.html

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.

Weakness

The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.

Potential Mitigations

Run the code in a “jail” or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.
This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.
Be careful to avoid CWE-243 and other weaknesses related to jails.

Incorrect Permission Assignment for Critical Resource

Weakness

Potential Mitigations

Related Attack Patterns

References