ssti-freemarker

Server-Side Template Injection in Java applications is exploited by injecting malicious template code to achieve Remote Code Execution or file reading. This Skill guides payload generation for engines like Freemarker, Velocity, Thymeleaf, Pebble, SpEL, Groovy, and Java EL.

Java template engines are identified by analyzing specific error messages and syntax variations. This Skill differentiates between Freemarker, Velocity, Thymeleaf, Pebble, Spring Expression Language, Groovy, and Java EL to determine the correct exploitation path.

Freemarker RCE payloads involve direct class execution and sandbox bypass techniques to execute commands on the server. This Skill provides specific payloads for Remote Code Execution, file reading, and bypassing template sandbox restrictions.

OPSEC considerations for Java process execution are included to maintain stealth during exploitation. The Skill provides operational security guidance tailored to the Java JVM and process execution behaviors when leveraging SpEL or Groovy injection.

Spring Expression Language injection can be used to read server files and achieve Remote Code Execution. This Skill provides specific SpEL payloads for file access and command execution within vulnerable Java applications.