Exploiting Template Injection Vulnerabilities

---
name: exploiting-template-injection-vulnerabilities
description: Use when detecting and exploiting Server-Side Template Injection (SSTI)
  vulnerabilities across Jinja2, Twig, Freemarker, and other template engines to achieve
  remote code execution. Use when working with exploiting template injection vulnerabilities.
domain: cybersecurity
tags:
- penetration-testing
- ssti
- template-injection
- rce
- web-security
- owasp
subdomain: web-application-security
version: '1.0'
author: oyi77
license: Apache-2.0
nist_csf:
- PR.PS-01
- ID.RA-01
- PR.DS-10
- DE.CM-01
category: cybersecurity
---

# Exploiting Template Injection Vulnerabilities

## Overview

Cybersecurity skill for exploiting template injection vulnerabilities. Follows industry best practices and security standards.

## When to Use
**Trigger phrases:**
- "exploiting template injection vulnerabilities"
- "Detecting and exploiting Server-Side Template Injection (SSTI) vulnerabilities a"


- During authorized penetration tests when user input is rendered through a server-side template engine
- When testing error pages, email templates, PDF generators, or report builders that include user-supplied data
- For assessing applications that allow users to customize templates or notification messages
- When identifying potential SSTI in parameters that reflect arithmetic results (e.g., `{{7*7}}` returns `49`)
- During security assessments of CMS platforms, marketing tools, or any application with templating functionality


## When NOT to Use

- When you lack proper authorization for testing
- For production systems without change management
- When the task requires legal or compliance expertise beyond technical scope


## Prerequisites

- **Authorization**: Written penetration testing agreement with RCE testing scope
- **Burp Suite Professional**: For intercepting and modifying template parameters
- **tplmap**: Automated SSTI exploitation tool (`git clone https://github.com/epinna/tplmap.git`)
- **SSTImap**: Modern SSTI scanner (`pip install sstimap`)
- **curl**: For manual SSTI payload testing
- **Knowledge of template engines**: Jinja2, Twig, Freemarker, Velocity, Mako, Pebble, ERB, Smarty

## Workflow

```python
# Example: IOC detection
import re

IOC_PATTERNS = {
    "ip": r"\b(?:\d{1,3}\.){3}\d{1,3}\b",
    "domain": r"\b[a-z0-9-]+\.[a-z]{2,}\b",
    "hash_md5": r"\b[a-f0-9]{32}\b",
    "hash_sha256": r"\b[a-f0-9]{64}\b",
}

def extract_iocs(text: str) -> dict:
    return {k: re.findall(v, text) for k, v in IOC_PATTERNS.items()}
```

1. **Reconnaissance** — Gather information about the target related to template injection vulnerabilities. Identify attack surface.
2. **Vulnerability Identification** — Enumerate potential template injection vulnerabilities weaknesses using automated and manual techniques.
3. **Exploit Development/Selection** — Choose or develop exploits targeting identified template injection vulnerabilities vulnerabilities.
4. **Execution** — Execute the template injection vulnerabilities test in a controlled manner with proper authorization.
5. **Post-Exploitation** — Document the impact and extent of successful exploitation.
6. **Reporting** — Write detailed findings with reproduction steps, impact assessment, and remediation guidance.

## Tools

- **Vulnerability Scanner** — Automated weakness identification
- **Exploitation Framework** — Controlled exploitation testing
- **Reporting Tool** — Findings documentation and tracking


## Process

1. **Reconnaissance** — Gather target information, identify attack surface, enumerate services
1. **Analysis/Exploitation** — Execute the technique, analyze results, document findings
1. **Reporting** — Document IOCs, write findings, provide remediation recommendations

## Verification

- [ ] All template injection vulnerabilities procedures executed completely and documented
- [ ] Findings validated against multiple data sources
- [ ] False positives identified and filtered
- [ ] Results documented with evidence and timestamps
- [ ] Recommendations provided with risk-based prioritization

## Anti-Rationalization Table

| Rationalization | Reality |
|---|---|
| "We are too small to be targeted" | Automated attacks target everyone. Size does not matter. |
| "Security slows us down" | A breach slows you down 100x more. Build security in from the start. |
| "We will fix it after launch" | Vulnerabilities in production are exploited within hours. Fix before deploy. |