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+# Creator Network Security Audit Checklist
+## Phase 3: Testing & Validation
+
+### 🔐 Authentication & Authorization
+
+- [ ] **JWT Validation**
+  - [ ] All protected endpoints require valid JWT token
+  - [ ] Expired tokens are rejected
+  - [ ] Invalid/malformed tokens return 401
+  - [ ] Token claims are validated before processing
+
+- [ ] **User Context Extraction**
+  - [ ] user_id is extracted from Supabase auth context (not request body)
+  - [ ] User cannot access/modify other users' data
+  - [ ] Session invalidation works properly on logout
+
+- [ ] **Authorization Checks**
+  - [ ] Creator can only update their own profile
+  - [ ] Opportunity creator can only update their own opportunities
+  - [ ] Applicant can only withdraw their own applications
+  - [ ] Only opportunity creator can review applications
+  - [ ] DevConnect links are user-specific
+
+### 🛡️ Row Level Security (RLS) Policies
+
+- [ ] **aethex_creators table**
+  - [ ] Users can read own profile
+  - [ ] Users can update own profile
+  - [ ] Public profiles are discoverable (is_discoverable=true)
+  - [ ] Private profiles (is_discoverable=false) are hidden from directory
+
+- [ ] **aethex_opportunities table**
+  - [ ] Anyone can read open opportunities
+  - [ ] Only creator can update/delete own opportunities
+  - [ ] Closed opportunities not visible to applicants
+
+- [ ] **aethex_applications table**
+  - [ ] Users can read their own applications
+  - [ ] Applicant can only see their own applications
+  - [ ] Opportunity creator can see applications for their opportunities
+  - [ ] Users cannot access others' applications
+
+- [ ] **aethex_devconnect_links table**
+  - [ ] Users can only access their own DevConnect links
+  - [ ] Links cannot be modified by non-owners
+
+- [ ] **aethex_projects table**
+  - [ ] Users can read public projects
+  - [ ] Users can only modify their own projects
+
+### 🔒 Data Protection
+
+- [ ] **Sensitive Data**
+  - [ ] Passwords are never returned in API responses
+  - [ ] Email addresses are not exposed in public profiles
+  - [ ] Private notes/applications are not leaked
+
+- [ ] **Cover Letters**
+  - [ ] Only applicant and opportunity creator can see cover letters
+  - [ ] Cover letters are not visible in search results
+
+- [ ] **Rate Limiting**
+  - [ ] Rate limiting is implemented on POST endpoints
+  - [ ] Prevents spam applications/profiles
+  - [ ] Prevents brute force attacks on search
+
+### 🚫 Input Validation & Sanitization
+
+- [ ] **Text Fields**
+  - [ ] Bio/description max length enforced (e.g., 500 chars)
+  - [ ] Username format validated (alphanumeric, dashes, underscores)
+  - [ ] HTML/script tags are escaped in output
+
+- [ ] **File Uploads**
+  - [ ] Avatar URLs are validated/whitelisted
+  - [ ] No malicious file types accepted
+  - [ ] File size limits enforced
+
+- [ ] **Array Fields**
+  - [ ] Skills array has max length
+  - [ ] Arm affiliations are from valid set
+  - [ ] Invalid values are rejected
+
+- [ ] **Numeric Fields**
+  - [ ] Salary values are reasonable ranges
+  - [ ] Page/limit parameters are validated
+  - [ ] Negative values rejected where inappropriate
+
+### 🔗 API Endpoint Security
+
+**Creators Endpoints:**
+- [ ] GET /api/creators
+  - [ ] Pagination parameters validated
+  - [ ] Search doesn't expose private fields
+  - [ ] Arm filter works correctly
+
+- [ ] GET /api/creators/:username
+  - [ ] Returns 404 if profile is not discoverable
+  - [ ] No sensitive data leaked
+
+- [ ] POST /api/creators
+  - [ ] Requires auth
+  - [ ] user_id extracted from auth context
+  - [ ] Duplicate username prevention works
+
+- [ ] PUT /api/creators/:id
+  - [ ] Requires auth
+  - [ ] User can only update own profile
+  - [ ] No privilege escalation possible
+
+**Opportunities Endpoints:**
+- [ ] GET /api/opportunities
+  - [ ] Only open opportunities shown
+  - [ ] Closed/draft opportunities hidden
+  - [ ] Pagination and filters work
+
+- [ ] GET /api/opportunities/:id
+  - [ ] Only returns open opportunities
+  - [ ] Creator info is sanitized
+
+- [ ] POST /api/opportunities
+  - [ ] Requires auth + creator profile
+  - [ ] user_id extracted from auth
+  - [ ] Only opportunity creator can post
+
+- [ ] PUT /api/opportunities/:id
+  - [ ] Requires auth
+  - [ ] Only creator can update own opportunity
+  - [ ] Can't change posted_by_id
+
+**Applications Endpoints:**
+- [ ] GET /api/applications
+  - [ ] Requires user_id + auth
+  - [ ] Users only see their own applications
+  - [ ] Opportunity creators can view applications
+
+- [ ] POST /api/applications
+  - [ ] Requires auth + creator profile
+  - [ ] Validates opportunity exists
+  - [ ] Prevents duplicate applications
+  - [ ] Validates cover letter length
+
+- [ ] PUT /api/applications/:id
+  - [ ] Requires auth
+  - [ ] Only opportunity creator can update
+  - [ ] Can only change status/response_message
+  - [ ] Can't change creator/opportunity
+
+- [ ] DELETE /api/applications/:id
+  - [ ] Requires auth
+  - [ ] Only applicant can withdraw
+  - [ ] Application is properly deleted
+
+**DevConnect Endpoints:**
+- [ ] POST /api/devconnect/link
+  - [ ] Requires auth + creator profile
+  - [ ] user_id from auth context
+  - [ ] Validates DevConnect username format
+
+- [ ] GET /api/devconnect/link
+  - [ ] Requires user_id + auth
+  - [ ] Users only see their own link
+  - [ ] Returns null if not linked
+
+- [ ] DELETE /api/devconnect/link
+  - [ ] Requires auth
+  - [ ] Only user can unlink their account
+  - [ ] Updates devconnect_linked flag
+
+### 🔍 SQL Injection Prevention
+
+- [ ] **Parameterized Queries**
+  - [ ] All Supabase queries use parameterized queries (not string concatenation)
+  - [ ] User input never directly in SQL strings
+  - [ ] Search queries are sanitized
+
+- [ ] **Search/Filter Safety**
+  - [ ] LIKE queries use proper escaping
+  - [ ] OR conditions properly scoped
+  - [ ] No SQL concatenation
+
+### 🌐 CORS & External Access
+
+- [ ] **CORS Headers**
+  - [ ] Only allowed origins can call API
+  - [ ] Credentials are properly scoped
+  - [ ] Preflight requests handled correctly
+
+- [ ] **External Links**
+  - [ ] DevConnect URLs validated
+  - [ ] Avatar URLs validated
+  - [ ] No javascript: or data: URLs allowed
+
+### 📋 Audit Logging
+
+- [ ] **Critical Actions Logged**
+  - [ ] User account creation
+  - [ ] Opportunity creation/deletion
+  - [ ] Application status changes
+  - [ ] DevConnect linking/unlinking
+  - [ ] Profile modifications
+
+- [ ] **Log Retention**
+  - [ ] Logs stored securely
+  - [ ] Logs retained for compliance period
+  - [ ] Sensitive data not logged
+
+### 🔄 API Response Security
+
+- [ ] **Error Messages**
+  - [ ] Don't leak system details
+  - [ ] Don't expose database structure
+  - [ ] Generic error messages for auth failures
+  - [ ] No stack traces in production
+
+- [ ] **Response Headers**
+  - [ ] X-Content-Type-Options: nosniff
+  - [ ] X-Frame-Options: DENY
+  - [ ] Content-Security-Policy set
+  - [ ] X-XSS-Protection enabled
+
+### 📱 Frontend Security
+
+- [ ] **Token Management**
+  - [ ] Tokens stored securely (not localStorage if possible)
+  - [ ] Tokens cleared on logout
+  - [ ] Token refresh handled properly
+
+- [ ] **XSS Prevention**
+  - [ ] User input escaped in templates
+  - [ ] No dangerouslySetInnerHTML without sanitization
+  - [ ] No eval() or similar dangerous functions
+
+- [ ] **CSRF Protection**
+  - [ ] State-changing requests use POST/PUT/DELETE
+  - [ ] CSRF tokens included where applicable
+
+### ✅ Testing Recommendations
+
+1. **Penetration Testing**
+   - Test SQL injection attempts
+   - Test XSS payloads in input fields
+   - Test CSRF attacks
+   - Test broken access control
+
+2. **Authorization Testing**
+   - Try accessing other users' resources
+   - Test privilege escalation attempts
+   - Verify RLS policies are enforced
+
+3. **Data Validation Testing**
+   - Send oversized inputs
+   - Send malformed data
+   - Test boundary values
+   - Send special characters
+
+4. **Rate Limit Testing**
+   - Rapid-fire requests
+   - Concurrent requests
+   - Verify limits are enforced
+
+### 📝 Sign-Off
+
+- [ ] All critical findings resolved
+- [ ] All high-priority findings mitigated
+- [ ] Security baseline established
+- [ ] Monitoring and logging active
+- [ ] Team trained on security practices
+
+---
+
+**Audit Date:** _________________
+**Auditor:** _________________
+**Status:** PENDING ⏳
+