The PHP web shell ‘Big Bang Bot’ contains the functionality to upload files. This can be useful to attackers who want to upload further pieces of malware to the vulnerable server. In addition, this server will display the username and current working directory when requested. An attacker can upload this shell to a server via an upload mechanism or vulnerability.
- An attacker uploads a PHP web shell to the vulnerable server via an upload mechanism or vulnerability.
- The server responds indicating a successful upload.
- The attacker acts upon objectives by utilizing the shell’s functionality.
The attacker must be able to send crafted packets to the target system.
Alert Logic Coverage
Alert Logic® has evaluated its customer base for exposure to the exploit and has developed signatures for mitigating the threat depending on the security service in place.
The Network-Based Intrusion Detection System (IDS) has been updated with the new signatures for this exploit when detected via Alert Logic Threat Manager™. If this signature is detected, an incident is generated in the Alert Logic console.
Recommendations for Mitigation
The attacker must have exploited some other entry vector to allow the malicious files to become resident on the victim machine.