Skip to main content

URL Inventory Management

Managing URL configurations in Zscaler ZIA becomes increasingly complex as lists grow to thousands of entries through multiple administrators, partner configurations, and emergency exceptions that become permanent.

Why URL Inventory Matters​

Security Risks:

  • Overly broad wildcards bypass security controls
  • Undocumented SSL exceptions create inspection blind spots
  • Configuration drift makes incident response slower

Operational Impact:

  • Troubleshooting takes 3-5x longer with messy URL configs
  • Policy changes require extensive testing
  • Knowledge transfer to new admins is difficult

Understanding URL Distribution in ZIA​

URLs appear in multiple locations across your configuration:

Primary Locations​

Custom URL Categories

  • SSL inspection exceptions
  • Custom allow/block lists
  • Application-specific groupings

Firewall Rules

  • Direct URL references without categories
  • Single-use allow rules
  • Partner/vendor specific rules

Advanced Settings

  • FTP control connections
  • Authentication exceptions
  • Malware protection exceptions

PAC Files

  • Direct proxy rules
  • Bypass lists
  • Complex routing logic

App Profiles

  • VPN gateway URLs
  • Cloud connector configurations

The URL Cleanup Process​

Phase 1: Export and Inventory​

Manual Method:

  1. Export each custom URL category (Administration > URL Categories > Export)
  2. Document URLs in firewall rules (review each rule manually)
  3. Check PAC files for hardcoded URLs
  4. Review App Profiles for gateway URLs

Create master spreadsheet with columns:

  • URL/FQDN
  • Source (category name, firewall rule, PAC file, etc.)
  • Date added (if available)
  • Requestor/reason

Time investment: 2-4 hours

Phase 2: Categorization Analysis​

Use Zscaler One API for bulk URL lookups to identify standard categories.

One API approach:

# Batch lookup (100 URLs per request)
response = requests.post(
    "https://api.zscaler.com/api/v1/urlLookup",
    headers={"Authorization": f"Bearer {token}"},
    json={"urls": urls_to_check}
)

Rate limits: 400 requests/day = 40,000 URLs/day capacity

Automated tools:

  • ZHERO: Automated URL export with categorization, policy impact, and wildcard detection - Learn more
  • Free Python Script: Manual URL analysis tool - GitHub

Add to inventory: Standard Zscaler categories for each URL

Time investment: 2-3 hours implementation + processing time

Phase 3: Wildcard Detection​

Review for wildcard patterns:

  • Starts with . → .example.com, .cdn.com
  • Contains * → *.example.com

Critical security check: Wildcards + SSL Exceptions + CDN Categories

Example finding:

*.akamaized.net in SSL exceptions = 2TB/month of bypassed traffic, millions of potential domains unin spected.

Remediation:

  1. Identify specific FQDNs needed (usually 5-15)
  2. Replace wildcard with specific entries
  3. Test thoroughly
  4. Document each exception

Time investment: 2-3 hours

Phase 4: Redundancy Identification​

Filter for URLs in block categories that belong to already-blocked standard categories.

Process:

  1. Filter inventory for custom block categories
  2. Cross-reference with Zscaler standard categories
  3. Check if standard categories already blocked in policies

Example: 1,422 URLs in "Block-Legacy" already belong to categories blocked elsewhere (pornography, gambling, unknown).

Time investment: 2-3 hours

Phase 5: Cleanup Execution​

Phase A: Quick Wins (Day 1-2)

  • Remove zero-impact URLs
  • Remove obvious redundant blocks
  • Test in report mode first (24-48 hours)

Phase B: Wildcard Consolidation (Day 3-4)

  • Replace CDN wildcards with specific FQDNs
  • Validate subdomain wildcards scope
  • Document all changes

Phase C: SSL Exception Optimization (Day 5-7)

  • Replace individual URLs with Cloud App exceptions where appropriate
  • Document business justification for each exception
  • Set quarterly review dates

Time investment: 5-7 days (including testing periods)

Phase 6: Documentation & Governance​

Maintain documentation in your master Excel/CSV inventory with these columns:

Essential columns:

  • URL/FQDN
  • Source (category name, firewall rule, etc.)
  • Owner (contact email)
  • Reason (why this URL needs exception/special handling)
  • Application/Business Purpose
  • Date Added
  • Next Review Date
  • Status (Active/Under Review/Scheduled for Removal)

Governance Process:

  1. All new exceptions require documentation in inventory
  2. Quarterly review of all exceptions
  3. Validate with owner to confirm still needed
  4. Remove exceptions no longer needed

This approach keeps documentation centralized and easy to audit.

Real-World Example: The CDN Wildcard Discovery​

During a routine SSL inspection quality audit, we discovered *.akamaized.net in a client's SSL exception category.

The Finding:

  • Traffic volume: 2TB/month (15% of total SSL bypass)
  • Risk: Millions of domains could bypass inspection
  • Root cause: Added 4 years ago, likely by partner during implementation
  • Documentation: None

The Investigation:

  • Good intentions: Legitimate apps use Akamai CDN
  • Wrong implementation: Wildcard instead of specific FQDNs
  • Lost context: No documentation on why, what apps, or when to review

The Remediation:

  1. Analyzed traffic logs → Identified 12 specific FQDNs actually needed
  2. Added specific entries to exception category
  3. Tested with pilot group (zero breaks)
  4. Removed wildcard
  5. Documented each specific exception with business owner

Result: 99.9% reduction in bypass scope, zero user impact, proper documentation established.

Disclaimer: Based on real technical findings observed across multiple Zscaler deployments. Details modified for client confidentiality.

Tools & Automation​

Manual Implementation:

  • ZIA Admin Portal (configuration)
  • Excel/Google Sheets (documentation)
  • One API (URL categorization lookups)
  • Calendar (review reminders)

ZHERO Automation:

  • Automated URL export with 20+ columns
  • Wildcard detection and related URL analysis
  • Policy impact tracking
  • Cloud app identification
  • Risk scoring and smart analysis

Learn more about ZHERO