cachex

README

Tool to detect cache poisoning vulnerabilities in Web API Endpoints

Features

• High-speed multi-threaded scanning
• Accurate detection of response manipulation and cache persistence
• Single and multi-header scan modes
• YAML-based payload configuration
• JSON or pretty output logging
• Optional file-based result export
• Tentative vs confirmed vulnerability tagging

Installation

go install github.com/ayuxdev/cachex/cmd/cachex@latest

Or build manually:

git clone https://github.com/ayuxdev/cachex
cd cachex
make build
./cachex -h

Usage

Scan a single URL

cachex -u https://example.com

Scan multiple targets

cachex -l urls.txt

Scan URLs piped from another command

echo "https://example.com" | cachex

or

cat urls.txt | cachex

All CLI Flags

Category	Flag	Description
Input	-u, --url	URL to scan
	-l, --list	File with list of URLs
Concurrency	-t, --threads	Number of threads to use
	-m, --scan-mode	single or multi header scan mode
HTTP Client	--timeout	Total request timeout
	--proxy	Proxy URL to use
Persistence Check	--no-chk-prst	Disable persistence check
	--prst-requests	Number of poisoning requests to send
	--prst-threads	Threads to use for persistence poisoning
Output	-o, --output	Output file (stdout if not specified)
	-j, --json	Enable JSON output
Payloads	--pcf	Path to custom payload config YAML

Example

cachex -l targets.txt -t 50 --pcf payloads.yaml --json -o results.json

Configuration

By default, these files are created:

• ~/.config/cachex/config.yaml
• ~/.config/cachex/payloads.yaml

You can configure:

• Custom payload headers
• Request headers
• Logging formats
• Concurrency and timeout
• Proxy and output preferences

Output Formats

Pretty Format

[vuln] [https://target.com] [Location Poisoning] [header: X-Forwarded-Host: evil.com] [poc: https://target.com?cache=XYZ]

JSON Format

{
  "URL": "https://target.com/",
  "IsVulnerable": true,
  "IsResponseManipulable": true,
  "ManipulationType": "ChangedBody",
  "RequestHeaders": {
    "Accept": "*/*",
    "User-Agent": "Mozilla/5.0"
  },
  "PayloadHeaders": {
    "X-Forwarded-Host": "evil.com"
  },
  "OriginalResponse": {
    "StatusCode": 200,
    "Headers": {
      "...": "..."
    },
    "Body": "...",
    "Location": ""
  },
  "ModifiedResponse": {
    "StatusCode": 200,
    "Headers": {
      "...": "..."
    },
    "Body": "...",
    "Location": ""
  },
  "PersistenceCheckResult": {
    "IsPersistent": true,
    "PoCLink": "https://target.example.com/?cache=XYZ",
    "FinalResponse": {
      "StatusCode": 200,
      "Headers": {
        "...": "..."
      },
      "Body": "...",
      "Location": ""
    }
  }
}

Scan Modes

• single: scans each payload header independently (more precise)
• multi: scans all payload headers together (faster, less precise)

Payload Headers

Defined in ~/.config/cachex/payloads.yaml. Includes:

payload_headers:
    Forwarded: for=127.0.0.1;host=evil.com;proto=https
    X-Client-IP: 127.0.0.1
    X-Custom-IP-Authorization: 127.0.0.1
    X-Forwarded-For: 127.0.0.1
    X-Forwarded-Host: evil.com
    X-Forwarded-Host-Override: evil.com
    X-Forwarded-Port: "443"
    X-Forwarded-Proto: https
    X-Forwarded-Scheme: https
    X-Forwarded-Server: evil.com
    X-HTTP-Method-Override: POST
    X-Host: evil.com
    X-Host-Override: evil.com
    X-Original-Host: evil.com
    X-Original-URL: /evilpath
    X-ProxyUser-Ip: 127.0.0.1
    X-Requested-With: XMLHttpRequest
    X-Rewrite-URL: /evilpath
    X-Url-Scheme: https

Configuration File (config.yaml)

By default, cachex reads configuration from ~/.config/cachex/config.yaml.

This allows fine-tuned control over scanning behavior without needing to pass flags every time.

Example config.yaml

scan_mode: single         # Scan mode: 'single' (more precise) or 'multi' (faster)
threads: 25               # Number of concurrent scanning threads

request_headers:          # Standard headers sent with every request (avoid adding payload or injection headers here to prevent scan issues)
  Accept: '*/*'
  User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Safari/537.36

client:
  dial_timeout: 5         # Dial timeout in seconds (TCP connection)
  handshake_timeout: 5    # TLS handshake timeout in seconds
  response_timeout: 10    # Max time to wait for a server response
  proxy_url: ""           # Optional proxy URL (e.g., http://127.0.0.1:8080)

persistence_checker:
  enabled: true             # Enable/disable persistence checking
  num_requests_to_send: 10  # Number of attempts to poison the cache
  threads: 5                # Threads to use for persistence scanning

logger:
  log_error: false        # Whether to log failed or errored requests
  log_mode: pretty        # Log format: 'pretty' (CLI-style) or 'json'
  debug: false            # Enable verbose debug logs
  output_file: ""         # File path to save output (leave blank for logging to stdout only)
  skip_tentative: true    # Skip logging tentative vulnerabilities

How It Works

1. Sends a baseline request
2. Injects headers and observes differences
3. Confirms cache persistence via repeat requests
4. Logs the vulnerability with optional PoC link

Contribute

Sure, PR's are welcome!

License

MIT © @ayuxdev