✅ Email Header Analysis Module (server/emailHeaderAnalyzer.js)
- DKIM (DomainKeys Identified Mail) verification
- SPF (Sender Policy Framework) validation
- DMARC (Domain-based Message Authentication) compliance checking
- Sender address mismatch detection
- Reply-To discrepancy analysis
- Suspicious header pattern detection
- Risk scoring algorithm (0-10 scale)
✅ Server API Endpoint (server/server.js)
- New
/api/analyze-email-headersPOST endpoint - Integration with emailHeaderAnalyzer module
- AI-enhanced analysis using Google Gemini
- Comprehensive response with risk assessment
✅ UI Enhancements (popup.html & popup.js)
- Tab-based interface (Page Analysis + Email Headers)
- Email header input text area
- Detailed results display with badges
- Risk score visualization
- Issues, warnings, and passed checks sections
- AI insights display
✅ Email Extractor (emailExtractor.js)
- Gmail header extraction support
- Outlook header extraction support
- Yahoo Mail header extraction support
- Generic email header extraction
- Instructions for accessing full headers
✅ Unit Tests (server/testEmailAnalyzer.js)
- 6 comprehensive test cases
- Coverage of all risk levels
- Verification of scoring algorithm
✅ Test Cases Document (EMAIL_HEADER_TESTS.md)
- Sample headers for testing
- Expected risk scores
- Real-world scenarios
- Instructions for all email providers
✅ User Guide (EMAIL_HEADER_GUIDE.md)
- Comprehensive feature explanation
- Step-by-step usage instructions
- Risk score interpretation
- Common phishing tactics
- Best practices
✅ Quick Reference (QUICK_REFERENCE.md)
- Quick start guide
- Visual risk score table
- Common red flags
- FAQ section
✅ Setup Guide (SETUP_GUIDE.md)
- Complete installation instructions
- Troubleshooting section
- File structure overview
- Testing procedures
✅ Updated README (README.md)
- Feature highlights
- Usage instructions for both features
- Risk level descriptions
✅ manifest.json
- Version bumped to 2.0
- Updated description to mention email header analysis
- Checks for DKIM signature presence
- Validates signature status from Authentication-Results
- Detects tampered emails
- Verifies sender server authorization
- Checks Received-SPF headers
- Identifies unauthorized senders
- Validates domain authentication policies
- Checks DMARC alignment
- Detects policy violations
- Compares From vs Return-Path domains
- Checks From vs Sender headers
- Identifies domain spoofing attempts
- Detects Reply-To discrepancies
- Identifies reply redirection attacks
- Warns about domain mismatches
- Automated mailer abuse detection
- Message-ID domain verification
- Date anomaly detection (future/old dates)
- Unusual routing pattern detection
- Google Gemini AI integration
- Contextual security assessment
- Human-readable explanations
- Actionable recommendations
The analyzer assigns risk scores from 0-10:
| Score | Risk Level | Color | Indicators |
|---|---|---|---|
| 0-3 | ✅ Safe | Green | All auth passed, no issues |
| 4-6 | Yellow | Some failures or warnings | |
| 7-10 | 🚨 High Risk | Red | Multiple failures, likely spoofing |
- DKIM fail: +3 points
- SPF fail: +3 points
- DMARC fail: +2 points
- Sender mismatch: +4 points
- Reply-To mismatch: +2 points
- Suspicious header: +1 point each
- Missing auth: +1 point each
- Maximum: 10 points
All 6 test cases pass with expected scores:
-
✅ Legitimate Email: Risk 0/10
- All authentication passed
- Consistent sender addresses
-
⚠️ SPF Failure: Risk 6/10- SPF failed
- Mismatched Return-Path
-
🚨 Multiple Failures: Risk 10/10 (capped)
- All authentication failed
- Multiple domain mismatches
-
⚠️ Reply-To Mismatch: Risk 2/10- Auth passed but Reply-To differs
- Domain mismatch warning
-
🚨 Future Date + Failures: Risk 10/10
- All auth failed
- Future-dated email
- Domain mismatches
-
⚠️ Missing Auth: Risk 3/10- No authentication headers
- Cannot verify sender
Chrome Extension (Frontend)
↓ (Paste headers)
popup.js (Parse headers)
↓ (HTTP POST)
Node.js Server (Backend)
↓
emailHeaderAnalyzer.js (Analysis)
↓
Google Gemini AI (Enhancement)
↓
Results → Display in Extension
emailHeaderAnalyzer.js:
analyzeEmailHeaders()- Main analysis functionanalyzeDKIM()- DKIM verificationanalyzeSPF()- SPF validationanalyzeDMARC()- DMARC checkingcheckSenderMismatch()- Sender verificationcheckReplyToMismatch()- Reply-To analysisdetectSuspiciousHeaders()- Pattern detectiongenerateEmailHeaderSummary()- Summary generation
server.js:
POST /api/analyze-email-headers- Analysis endpointcreateEmailAnalysisPrompt()- AI prompt generation
popup.js:
parseEmailHeaders()- Header parsinganalyzeEmailHeaders()- Trigger analysisdisplayEmailResult()- Render results
-
Access Email Headers
- Open suspicious email
- Use provider-specific menu to view headers
- Copy raw header text
-
Analyze
- Open extension
- Switch to "Email Headers" tab
- Paste headers
- Click "Analyze"
-
Review Results
- Check risk score
- Review authentication status
- Read issues and warnings
- Follow AI recommendations
-
Take Action
- Score 0-3: Likely safe to proceed
- Score 4-6: Verify through official channels
- Score 7-10: Report and delete
The tool helps users understand:
- How email authentication works
- What DKIM, SPF, DMARC mean
- How to identify spoofed emails
- Technical indicators of phishing
- Importance of email security
- Headers analyzed locally and via Google AI
- No permanent data storage
- No email content analyzed (only headers)
- API key secured in .env file
- CORS protection on server
- Input sanitization and validation
Potential additions:
- Bulk header analysis
- Historical tracking of sender patterns
- Direct integration with webmail via content scripts
- Export analysis reports
- Custom rule configuration
- Database of known phishing domains
- Machine learning for pattern recognition
server/emailHeaderAnalyzer.js- Core analysis engineserver/server.js- Updated with new endpointemailExtractor.js- Webmail header extractorpopup.html- Updated UI with tabspopup.js- Updated with email analysismanifest.json- Updated version and descriptionserver/testEmailAnalyzer.js- Unit tests
EMAIL_HEADER_GUIDE.md- Comprehensive user guideEMAIL_HEADER_TESTS.md- Test cases and samplesQUICK_REFERENCE.md- Quick reference cardSETUP_GUIDE.md- Installation and setupREADME.md- Updated with new features
The email header analysis feature is now fully integrated into the Phishing Detector extension. It provides:
- Comprehensive Analysis: Checks 6+ security indicators
- AI-Enhanced: Leverages Google Gemini for insights
- User-Friendly: Clear risk scores and explanations
- Well-Tested: 6 test cases covering all scenarios
- Well-Documented: 5 comprehensive documentation files
- Production-Ready: Fully functional and tested
Users can now analyze both webpages and email headers for phishing indicators, making this a complete phishing detection solution!
To start using the feature:
- Follow
SETUP_GUIDE.mdfor installation - Read
QUICK_REFERENCE.mdfor quick start - Try test cases from
EMAIL_HEADER_TESTS.md - Refer to
EMAIL_HEADER_GUIDE.mdfor detailed information
Happy phishing detection! 🛡️