SSL VPN Client Remote Code Execution Scanner

SSL VPN Client is a software application widely used across enterprise environments for secure remote access to organizational networks. It facilitates encrypted connections and ensures that users can safely access corporate resources from remote locations. Developed with ease of use and security in mind, SSL VPN Client is integrated into many network infrastructures to provide robust virtual private network services. Commonly employed by IT departments and managed service providers, the client supports both small to large scale deployments. Its accessibility and integration features make it a preferred choice for businesses looking to maintain secure remote connectivity. The SSL VPN Client is especially important in contexts where secure access to sensitive data is required.

The detected vulnerability, Remote Code Execution (RCE), is a critical security issue that allows an attacker to execute arbitrary code on a vulnerable system. This kind of vulnerability significantly undermines system integrity and can lead to unauthorized access and control over affected systems. A successful exploitation of an RCE vulnerability can result in the deployment and execution of malicious payloads, potentially leading to data theft or system disruption. Remote Code Execution vulnerabilities are especially dangerous due to their potential for exploitation over the internet, allowing attackers to compromise systems from anywhere in the world. The ability for an attacker to run commands at their discretion presents a severe risk to organizational security. Identification and remediation of RCE vulnerabilities are of utmost importance to safeguard networks and data.

The technical details of the vulnerability in the SSL VPN Client involve leveraging a vulnerable endpoint that improperly handles user input, thereby allowing an attacker to concatenate system commands. The vulnerable endpoint in this case is "/sslvpn/sslvpn_client.php?client=logoImg&img". This parameter can be manipulated to execute shell commands by injecting code that the server interprets and runs. The flaw lies in inadequate input validation, where special characters or command sequences are executed directly by the server. In this template, the payload aims to execute the 'id' command to read user and group information on the target system. Once targeted, the output is stored and potentially retrieved using predictable file paths, facilitating unauthorized code execution.

Exploitation of this Remote Code Execution vulnerability could allow an attacker to gain complete control of the affected server. This may result in unauthorized access to sensitive information, data breaches, and the potential to distribute malware within the internal network. Furthermore, an attacker could disrupt services and degrade network performance through sustained attacks leveraging this vulnerability. Organizations may face reputational and financial damages as a result of such exploits. Thus, detecting and mitigating RCE vulnerabilities is vital for maintaining system security and defending against malicious activities.

REFERENCES

• https://github.com/server2565543706/Poc/blob/master/POC/anquantongsha.py
• https://github.com/Vme18000yuan/FreePOC/blob/master/poc/pocsuite/security_products_rce.py