Source: cna@vuldb.com
A vulnerability was detected in HummerRisk up to 1.5.0. This affects the function CommandUtils.commonExecCmdWithResult of the file CloudTaskService.java of the component Cloud Task Dry-run. Performing a manipulation of the argument fileName results in command injection. Remote exploitation of the attack is possible. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
HummerRisk version 1.5.0 and below is vulnerable to a critical command injection flaw, allowing attackers to execute arbitrary commands on the server. This vulnerability, stemming from improper input validation in the CloudTaskService.java file, can lead to complete system compromise and data exfiltration.
Step 1: Payload Delivery: An attacker crafts a malicious fileName argument containing a command injection payload (e.g., '; whoami; ').
Step 2: Request Submission: The attacker submits the crafted fileName argument to the vulnerable CloudTaskService.java component, likely through a web request or API call.
Step 3: Command Execution: The commonExecCmdWithResult function receives the malicious fileName and, due to the lack of sanitization, executes the injected command as part of a system command.
Step 4: Command Output: The server executes the attacker's command. The output of the command (e.g., the username) is likely returned to the attacker, or the attacker can use the command to download a reverse shell.
Step 5: System Compromise: The attacker leverages the command execution to gain further access, potentially escalating privileges, installing malware, or exfiltrating sensitive data.
The vulnerability lies within the CommandUtils.commonExecCmdWithResult function, specifically when handling the fileName argument within the CloudTaskService.java component. The root cause is a lack of proper input sanitization or validation of the fileName parameter before it's used in a system command execution. This allows an attacker to inject malicious commands into the fileName argument, which are then executed by the server. The function likely uses a system call (e.g., Runtime.getRuntime().exec()) to execute the command, making the injection directly exploitable. The absence of vendor response further exacerbates the risk.
While no specific APTs are directly linked to this CVE, the public availability of the exploit and the severity of the vulnerability make it attractive to various threat actors. This vulnerability could be leveraged by ransomware groups, nation-state actors, and financially motivated cybercriminals. This vulnerability is likely to be added to the CISA KEV list soon.
Monitor web server logs for suspicious requests to the CloudTaskService.java endpoint, particularly those containing unusual characters or command injection attempts in the fileName parameter.
Analyze network traffic for unusual outbound connections originating from the server, especially to suspicious IP addresses or domains.
Implement file integrity monitoring to detect any unauthorized modifications to critical system files.
Use intrusion detection/prevention systems (IDS/IPS) with signatures specifically designed to detect command injection attempts.
Monitor system process activity for suspicious processes or command executions.
Implement input validation and sanitization: Thoroughly validate and sanitize the fileName parameter to prevent command injection. This includes blacklisting or whitelisting specific characters and validating the file name format.
Use parameterized queries or prepared statements: If possible, use parameterized queries or prepared statements to prevent command injection.
Apply the principle of least privilege: Run the application with the minimum necessary privileges to limit the impact of a successful exploit.
Update to a patched version: If a patched version of HummerRisk is available, upgrade immediately.
Implement a Web Application Firewall (WAF): Deploy a WAF to filter malicious requests and prevent command injection attempts.
Review and harden server configurations: Ensure that the server is configured securely, with unnecessary services disabled and security best practices followed.