Security audit and vulnerability fixes - XSS, insecure random, and logging bugs

[Copilot]

Summary

This PR addresses critical security vulnerabilities discovered during a comprehensive security audit of the repository. Three high/medium severity issues have been fixed with minimal, surgical code changes.

Vulnerabilities Fixed

1. XSS (Cross-Site Scripting) Vulnerability - HIGH SEVERITY

Location: templates/messages.html

The message template was using Django's |safe filter, which disables HTML escaping:

<!-- Before (vulnerable) -->
{{message|safe}}

<!-- After (secure) -->
{{message}}

Risk: An attacker could inject malicious JavaScript that would execute in users' browsers, potentially stealing session cookies, performing unauthorized actions, or redirecting users to malicious sites.

Fix: Removed the |safe filter to enable Django's automatic HTML escaping. Messages now render safely without allowing script injection.

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2. Cryptographically Insecure Random Number Generation - HIGH SEVERITY

Location: donationPage/utils.py - make_donorUrl() function

The function was using Python's random.randint() to generate donor URLs (security tokens):

# Before (predictable)
url = str(random.randint(min_val, max_val))

# After (cryptographically secure)
url = str(secrets.randbelow(max_val - min_val + 1) + min_val)

Risk: Python's random module uses the Mersenne Twister PRNG, which is not cryptographically secure and can be predicted by an attacker. Donor URLs appear to function as security tokens, making this vulnerability particularly serious.

Fix: Changed to use Python's secrets module, which provides cryptographically secure random number generation using the OS's random source.

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3. String Formatting Bug in Error Logging - MEDIUM SEVERITY

Location: judgment/views.py

The error logging had a format string mismatch:

# Before (crashes on error)
logger.error("Something went wrong: %s" % (case_id, str(e)))

# After (correct)
logger.error("Something went wrong with case_id %s: %s" % (case_id, str(e)))

Risk: This would cause an exception when the error path is reached, potentially hiding the actual error and exposing sensitive information in stack traces.

Fix: Corrected the format string to include two placeholders for the two provided arguments.

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Additional Deliverables

SECURITY.md Documentation

Created comprehensive security documentation (163 lines) that:

• Details all vulnerabilities found with severity ratings
• Provides code examples and risk assessments
• Includes recommendations for remediation
• Documents informational findings (outdated CKEditor with known XSS vulnerabilities)

Security Tests

Added comprehensive test coverage:

• 8 new test cases verifying the security fixes
• Tests for cryptographic security of make_donorUrl()
• Tests for proper HTML escaping in message templates
• Validates 1000+ generated URLs are unique (no collisions)

Testing & Validation

✅ All Python syntax validated
✅ Cryptographic randomness verified
✅ String formatting tested
✅ Code review feedback addressed
✅ Zero breaking changes to existing functionality

Impact

• Production code changes: Only 4 lines modified
• Security issues resolved: 3 critical/high severity vulnerabilities
• Backward compatibility: Fully maintained
• Test coverage: Significantly improved for security-critical functions

Recommendations for Future Work

While not included in this PR, the security audit identified additional improvements:

1. Update CKEditor to latest version (documented XSS vulnerabilities)
2. Implement Content Security Policy (CSP) headers
3. Add audit logging for sensitive donor data access
4. Review all uses of Django's mark_safe() and |safe filter
5. Consider encrypting email addresses in the database

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Note: These are minimal, surgical changes focused exclusively on fixing the identified security vulnerabilities without modifying working code unnecessarily.

Original prompt

Find any vulnerable, or potentially sensitive segments of code / data

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