Exploited. On CISA's list since 2025-06-02.

ASUS RT-AX55 Routers OS Command Injection Vulnerability

CVE-2023-39780 · ASUS RT-AX55 Routers · Published 2023-09-11

How bad would it be?

8.8 out of 10

CVSS rates it high.

How likely is it to be used?

40%

Estimated chance of exploitation in the next 30 days, higher than 98% of all scored flaws (EPSS, 2026-10-29).

Is it already being used?

Yes

CISA has seen it exploited in real attacks. For US government agencies the fix is deadline passed 494 days ago (2025-06-23).

What CISA says to do

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

ASUS RT-AX55 devices contain an OS command injection vulnerability that could allow a remote, authenticated attacker to execute arbitrary commands. As represented by CVE-2023-41346.

What the flaw is

On ASUS RT-AX55 3.0.0.4.386.51598 devices, authenticated attackers can perform OS command injection via the /start_apply.htm qos_bw_rulelist parameter. NOTE: for the similar "token-generated module" issue, see CVE-2023-41345; for the similar "token-refresh module" issue, see CVE-2023-41346; for the similar "check token module" issue, see CVE-2023-41347; and for the similar "code-authentication module" issue, see CVE-2023-41348.

From the NVD.

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OS command injection

Input changes a command that the server runs through its operating system.

CWE-78 · CISA KEV; NVD record: cve@mitre.org; NVD record: nvd@nist.gov

Reading and practice labs · Free account for labs. Basic HTTP knowledge; some labs use Burp Suite.

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Exploited flaws from CISA's KEV catalogue. Chance of exploitation from EPSS by FIRST. Descriptions and scores from the NVD. This product uses the NVD API but is not endorsed or certified by the NVD.