phishsage 1.0.0.post3

Lightweight email triage and phishing-analysis toolkit. Extracts headers, attachments, and links, applies heuristic checks, and produces structured insights.

PhishSage

PhishSage is a lightweight phishing-analysis toolkit that parses raw emails, inspects headers, analyzes links and domains with multi-layer heuristics, and outputs structured JSON findings for fast, automated investigation

1. Core functionality

PhishSage is intentionally minimal and concentrates on these essential capabilities:

• Header analysis

  • Extracts normalized sender-related headers (From, Reply-To, Return-Path, Message-ID)
  • Parses SPF, DKIM, and DMARC results from Authentication-Results
  • Performs alignment checks across From, Reply-To, and Return-Path
  • Validates Message-ID domain consistency
  • Checks timestamp sanity: Date header vs first Received hop
  • Looks up WHOIS domain age and flags newly registered domains
  • Validates MX records for the From domain
  • Queries Spamhaus DBL for sender-related domains
  • Aggregates all findings into structured JSON with merged alerts

• Attachment processing

  • List attachments with MIME and size
  • Extract attachments safely (avoid overwrites)
  • Compute hashes (MD5, SHA1, SHA256)
  • Optional VirusTotal scan by SHA256
  • Scan attachments with YARA rules (single files, multiple files, or directories; recursive and filtered for valid .yar/.yara files)
  • Verbose mode shows matched strings with offsets and hex data

• Link / URL analysis

  • Extracts URLs from email bodies or headers
  • Detects URLs using raw IP addresses instead of domains
  • Flags suspicious or uncommon top-level domains (TLDs)
  • Identifies excessive or nested subdomains, ignoring trivial ones (e.g., "www")
  • Recognizes shortened URLs (bit.ly, tinyurl.com, etc.)
  • Calculates Shannon entropy for domain and subdomain to spot obfuscation
  • Performs SSL/TLS certificate inspection (issuer, validity, domain match, expiration)
  • Looks up domain age via WHOIS and flags newly registered or expiring domains
  • VirusTotal URL lookup for threat intelligence
  • Optional redirect-chain tracing to uncover hidden destinations
  • Checks for numeric-only registrable domains
  • Detects URLs hosted on free or cheap hosting platforms
  • Flags URLs with excessively deep paths

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2. Environment Setup

# 1. (Optional) Create and activate a virtual environment
python3 -m venv venv

# Linux / macOS
source venv/bin/activate

# Windows (PowerShell)
venv\Scripts\Activate.ps1

# 2. Install PhishSage from PyPI
pip install phishsage

# 3. (Optional) Set VirusTotal API key
export VIRUSTOTAL_API_KEY="your_virustotal_api_key"     # Linux/macOS

# Windows (PowerShell)
# setx VIRUSTOTAL_API_KEY "your_virustotal_api_key"

3. CLI Usage

PhishSage provides a command-line interface with three main modes: headers, attachment, and links. The headers and links modes output results in JSON format, while the attachment mode produces human-readable summaries only.

Main Help

phishsage -h

Output:

usage: phishsage [-h] {headers,attachment,links} ...

PhishSage

positional arguments:
  {headers,attachment,links}
    headers             Analyze email headers for anomalies or indicators
    attachment          Analyze or extract attachments
    links               Analyze links in email content

options:
  -h, --help            show this help message and exit

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Header Analysis

phishsage headers -h

Options:

usage: phishsage headers [-h] -f FILE [--heuristics] [--json]

options:
  -h, --help       show this help message and exit
  -f, --file FILE  Email file to analyze (.eml)
  --heuristics     Run heuristic header analysis for anomalies
  --json           Output results in raw JSON format

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Attachment Processing

phishsage attachment -h

Options:

usage: phishsage attachment -f FILE [--list] [--extract DIR] [--hash] [--scan] [--yara PATH [PATH ...]] [--yara-verbose] [--json]

options:
  -h, --help              show this help message and exit
  -f, --file FILE         Email file to analyze (.eml)
  --list                  List attachments only
  --extract DIR           Extract attachments to specified directory
  --hash                  Compute hashes (MD5, SHA1, SHA256) for each attachment
  --scan                  Check attachments against VirusTotal by SHA256
  --yara PATH [PATH ...]  Scan attachments with YARA rules. Paths can be files or directories; directories are scanned recursively for .yar/.yara files.
  --json                  Output results in raw JSON format

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Link / URL Analysis

phishsage links -h

Options:

usage: phishsage links [-h] -f FILE [--extract] [--scan]  [--check-redirects | --heuristics] [--include-redirects] [--json]

options:
  -h, --help           show this help message and exit
  -f, --file FILE      Email file to analyze (.eml)
  --extract            Extract all URLs found in the email body or headers
  --scan               Submit extracted links to VirusTotal for analysis
  --check-redirects    Follow and display final redirect destinations for each URL
  --heuristics         Run phishing heuristics on extracted URLs
  --include-redirects  Include redirect chain when running heuristics (ignored if --heuristics not used)
  --json               Output results in raw JSON format

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4. Configuration

PhishSage stores configuration values in the project config (config.toml) or environment variables. The main items you may safely adjust are:

• VIRUSTOTAL_API_KEY — API key for VirusTotal scans.
• MAX_REDIRECTS — Maximum number of redirects to follow when checking redirect chains.
• THRESHOLD_YOUNG, THRESHOLD_EXPIRING — Domain age/expiry thresholds (in days). Domains younger than THRESHOLD_YOUNG or expiring within THRESHOLD_EXPIRING days are flagged as potentially suspicious.
• FREE_HOSTING_PROVIDERS, SUSPICIOUS_TLDS, SHORTENERS — Heuristic lists used in URL/link analysis.
• SUBDOMAIN_THRESHOLD, TRIVIAL_SUBDOMAINS — Used for subdomain heuristics to identify excessive or meaningful subdomains.
• FREE_EMAIL_DOMAINS — Free email providers that may indicate disposable or less-trusted addresses.
• DATE_RECEIVED_DRIFT_MINUTES — Maximum allowed difference between the Date header and the first Received hop in email headers.

Note: Only modify thresholds or heuristic lists if you understand the potential impact on false positives and overall detection accuracy.

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5. Scope & Limitations

• Focused functionality: PhishSage is not a full mail forensic suite. It prioritizes heuristics, quick triage, and enrichment over deep forensic analysis.
• Network-dependent checks: WHOIS, VirusTotal, MX, and SSL inspections rely on external services; results may vary or fail due to connectivity issues or API limits.
• Attachment processing: Currently limited to listing, extraction, hashing, and optional VirusTotal scans. Full heuristic attachment analysis will be introduced in a future release.
• Output formats: JSON output is available for all modes.
• Intended use: Designed for investigative support and enrichment. Not intended for automated blocking or enforcement in production email systems.
• Evolving coverage: Current checks under each section are limited; additional heuristics and enhanced analyses will be added in future releases.

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6. Contributing

Contributions to PhishSage are welcome! You can help improve the project by:

• Adding or refining heuristic checks for headers, attachments, and links.
• Expanding the lists in config.toml.
• Improving parsing, normalization, or output handling.
• Reporting bugs or suggesting enhancements.

Before submitting changes, please ensure they are well-tested and maintain the code’s clarity, security, and reliability. Contributions that enhance detection coverage, reduce false positives, or improve usability are particularly appreciated.