CVE-2025-45491: Critical Command Injection Vulnerability in Linksys E5600

Overview

In the evolving cybersecurity landscape, a critical vulnerability has been identified in the Linksys E5600 v1.1.0.26, labeled as CVE-2025-45491. This vulnerability, if exploited, could potentially lead to system compromise or data leakage. It affects users of the Linksys E5600 v1.1.0.26 device, a popular router used in many homes and small businesses. It’s an alarming issue due to the high CVSS Severity Score of 9.8, indicating a severe threat to the security of users’ data and systems.

Vulnerability Summary

CVE ID: CVE-2025-45491
Severity: Critical (9.8 CVSS Severity Score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: System compromise or data leakage

Affected Products

Product | Affected Versions

Linksys E5600 | v1.1.0.26

How the Exploit Works

The CVE-2025-45491 vulnerability exists due to the improper sanitization of the username parameter in the runtime.ddnsStatus DynDNS function. This allows an attacker to inject arbitrary commands into the system through this parameter, which will then be executed with high-level privileges. The attacker can exploit this vulnerability remotely over a network, without requiring any user interaction or privileges.

Conceptual Example Code

Below is a conceptual example of how the vulnerability might be exploited. An attacker sends a malicious HTTP request with the injected command in the username parameter:

POST /runtime.ddnsStatus HTTP/1.1
Host: target.example.com
Content-Type: application/json
{ "username": "; [insert malicious command here]" }

In this example, the semicolon allows the attacker to inject a new command into the username parameter, which is then executed by the system.

Mitigation

To mitigate this vulnerability, users are advised to apply the patch provided by the vendor as soon as it becomes available. In the meantime, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can provide temporary mitigation. This will prevent the execution of malicious commands and provide an additional layer of security until a permanent solution can be implemented.