# Performing Cryptographic Audit Of Application

> Perform performing cryptographic audit of application assessment during authorized security testing. Use this skill when indicators of the vulnerability class are present in the target environment.

- Skill: `wufufu770/performing-cryptographic-audit-of-application` (Agent Skill)
- Install (CLI): `npx skillmds@latest add wufufu770/performing-cryptographic-audit-of-application`
- Raw SKILL.md: https://api.skillmd.com/api/skills/wufufu770/performing-cryptographic-audit-of-application/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Security
- License: Apache-2.0
- Author: wufufu770 (https://skillmd.com/u/wufufu770)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/wufufu770/performing-cryptographic-audit-of-application

---


## TL;DR

- **目的**：A cryptographic audit systematically reviews an application's use of cryptographic primitives, protocols, and key management to identify vul…
- **适用**：云/K8s/容器/配置审计
- **输入**：目标 URL + 端点/参数清单
- **输出**：配置审计报告 + 修复建议
- **红线**：仅限授权范围内；扫描限速 `-c 10 -rl 10`；所有动作记 oplog
- **关联**：上游：003-src-session-start → 下游：043-hunt-nosqli, 027-hunt-cors, 028-hunt-csrf

# Performing Cryptographic Audit of Application

## Quick Start

```bash
# 通用 Web 漏洞测试命令
curl -v http://target.com | head -20
```

## Overview

A cryptographic audit systematically reviews an application's use of cryptographic primitives, protocols, and key management to identify vulnerabilities such as weak algorithms, insecure modes, hardcoded keys, insufficient entropy, and protocol misconfigurations. This skill covers building an automated crypto audit tool that scans Python and configuration files for common cryptographic weaknesses.


## When to Use

- When conducting security assessments that involve performing cryptographic audit of application
- When following incident response procedures for related security events
- When performing scheduled security testing or auditing activities
- When validating security controls through hands-on testing

## Prerequisites

- Familiarity with cryptography concepts and tools
- Access to a test or lab environment for safe execution
- Python 3.8+ with required dependencies installed
- Appropriate authorization for any testing activities

## Objectives

- Detect usage of deprecated algorithms (MD5, SHA-1, DES, RC4)
- Identify insecure cipher modes (ECB) and padding schemes
- Find hardcoded keys, passwords, and secrets in source code
- Verify TLS/SSL configuration strength
- Check key derivation function parameters
- Validate random number generator usage
- Produce a structured audit report with findings and remediation

## Key Concepts

### Cryptographic Weakness Categories

| Category | Examples | Risk Level |
|----------|----------|------------|
| Weak Hashing | MD5, SHA-1 for integrity/signatures | High |
| Insecure Encryption | DES, 3DES, RC4, Blowfish | High |
| Bad Cipher Mode | ECB mode for any block cipher | High |
| Insufficient Key Size | RSA < 2048, AES-128 for long-term | Medium |
| Hardcoded Secrets | Keys/passwords in source code | Critical |
| Weak KDF | Low iteration PBKDF2, plain MD5 | High |
| Poor Entropy | time-based seeds, predictable IVs | High |
| Deprecated Protocols | SSLv3, TLS 1.0, TLS 1.1 | High |

## Security Considerations

- Review both application code and configuration files
- Check third-party dependencies for known crypto vulnerabilities
- Verify certificates and TLS configurations on deployed servers
- Ensure secrets are loaded from environment variables or vaults
- Review key storage and rotation practices

## Validation Criteria

- [ ] Scanner detects all injected test weaknesses
- [ ] MD5/SHA-1 usage for security purposes is flagged
- [ ] ECB mode usage is flagged
- [ ] Hardcoded keys/passwords are detected
- [ ] Weak KDF parameters are identified
- [ ] Report includes severity, location, and remediation
- [ ] False positive rate is below 10%

## Output Format

```json
{
  "vulnerability_type": "<class>",
  "endpoint": "<URL with vulnerable parameter>",
  "poc": "<minimal reproducible payload>",
  "impact": "<data disclosed / privilege / RCE / bypass>",
  "cvss_score": "<0.0-10.0>",
  "remediation": "<concise fix recommendation>"
}
```

Save findings to `share/intel/findings/<target>-<timestamp>.md` and follow the report template selected at session start.

## Workflow

1. **Recon** — Identify the target endpoint via `96-osint-methodology` or `009-osint-with-spiderfoot`
2. **Fingerprint** — Confirm component/version using `01-component-nday` or Burp Suite passive detection
3. **Probe** — Send payload variations matching the vulnerability class
4. **Verify** — Run `111-fp-check` to confirm with second tool
5. **Document** — Fill report template (project-pentest / cnvd-common / edusrc / butian)
6. **Submit** — Manual submission (never auto-submit)
## Tools & Systems

- **Burp Suite Pro / Community** — Intercepting proxy, scanner, and Repeater for manual testing
- **OWASP ZAP** — Open-source alternative to Burp with active scanner
- **sqlmap** — Automated SQL injection detection (for hunt-sqli)
- **Nuclei** — Template-based vulnerability scanner
- **ffuf** — Fast web fuzzer for endpoint discovery
- **curl / wget** — Manual HTTP request crafting
- **httpx** — HTTP probing and fingerprinting

Run all tools with `-rate-limit 20` to avoid OPSEC issues. For deeper investigation, prefer manual testing with Burp over automated scanners (lower false-positive rate).


## Advanced Techniques

### Chained Vulnerability Exploitation
Combine multiple low-severity findings (open redirect + cookie theft + session hijacking) to demonstrate high-impact chains in reporting.

### WAF Evasion Patterns
Use case variations, encoding (URL, double-URL, Unicode), chunked transfer, and parameter pollution to bypass WAF/IDS during testing.