# CVE-2023-39780: ASUS RT-AX55 OS command injection in start_apply.htm

Source: https://junglewise.ai/threats/cve-2023-39780-asus-rt-ax55-os-command-injection-in-start-apply-htm  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-06-02. Updated: 2026-05-15  
License: CC BY 4.0 with a link back

CVE-2023-39780 · Severity: critical · CVSS 8.8 · Exploited in the wild · Published 2025-06-02

ASUS RT-AX55 wireless routers are affected by a security flaw that allows an authorized user to take complete control of the device. By sending specially crafted data to the router's management interface, an attacker can execute system-level commands. This could lead to the interception of internet traffic, unauthorized access to the local network, or a total disruption of internet services.

Vendors: [ASUS](https://junglewise.ai/threats/vendors/asus).

## Quick answers

**Is CVE-2023-39780 exploited in the wild?** Yes. CVE-2023-39780 is known to be exploited in the wild, first recorded on 2 June 2025. Treat it as urgent.

**How severe is CVE-2023-39780?** Critical severity, with a CVSS score of 8.8, published 2 June 2025.

**Which products and versions are affected?** ASUS RT-AX55 3.0.0.4.386.51598.

**Is there a fix for CVE-2023-39780?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2023-39780 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2023-39780?** Check whether you run ASUS RT-AX55 or ASUS Rt-Ax55 Routers at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

An OS command injection vulnerability (CWE-78) exists in ASUS RT-AX55 routers running firmware version 3.0.0.4.386.51598. The flaw is located in the '/start_apply.htm' endpoint via the 'qos_bw_rulelist' parameter, which fails to properly sanitize user input before passing it to a system shell. A remote attacker with low-privileged authentication can exploit this to execute arbitrary commands with elevated privileges on the underlying Linux operating system. This vulnerability has been observed in the wild as part of stealthy backdoor campaigns. Users are advised to update to the latest firmware version provided by ASUS.

## Affected products

- ASUS RT-AX55 3.0.0.4.386.51598

## Timeline

- 2023-09-14: disclosed: Initial NVD analysis published
- 2025-06-02: kev added: Added to CISA Known Exploited Vulnerabilities catalog
- 2025-06-02: exploited: Confirmed active exploitation in the wild