Full Report
The Dangerous websites Warning List will soon be five years old. Over this time it stopped millions of attempts to connect to malicious domains and has become our most effective tool in the fight against phishing websites.
Analysis Summary
# Industry News: CERT Polska Deprecates Legacy Phishing Warning List Version 1
## Summary
CERT Polska is formally deprecating the first version (v1) of its highly effective Dangerous Websites Warning List, which has blocked millions of phishing attempts over nearly five years. Integrators must transition to the new v2 format by June 1, 2025, which offers more precise blocking and implements automatic 6-month data retention.
## Key Details
- **Date:** Announcement made January 2, 2025; Deprecation effective June 1, 2025.
- **Companies Involved:** CERT Polska (part of the Polish operational CSIRT).
- **Category:** Product Update/Service Sunset (Standardization/Migration).
## The Story
CERT Polska's Dangerous Websites Warning List (DWWL) has been a crucial defensive tool against malicious domains, particularly phishing sites. Recognizing the need for modernization, CERT Polska introduced Version 2 (v2) over a year ago. This v2 list resolves issues present in v1, such as the outdated practice where some integrators continued blocking expired entries. The deprecation deadline of June 1, 2025, requires all systems relying on the legacy URLs (e.g., `/domains.txt`) to update their pointers to the new structure (e.g., `/v2/domains.txt`). A key technical change in v2 is the automated data retention policy, ensuring lists only contain data from the last six months, thereby promoting the blocking of *currently* active threats.
## Business Impact
### For the Companies Involved
- **CERT Polska:** Streamlines maintenance, modernizes infrastructure, and improves data quality enforcement by ensuring users rely only on current data via the automated retention policy.
### For Competitors
- **Other National CERTs/Security Vendors:** This standardization reflects a broader industry trend toward time-bound threat intelligence feeds. While CERT Polska is the operator making the change, it sets a precedent for how public threat feeds should be managed (i.e., no stale data).
### For Customers
- **Integrators/End Users (Organizations using the list):** Requires mandatory development effort to update API calls or configuration files before the June 2025 deadline to maintain threat protection capabilities. Failure to update will result in service interruption (receiving a 301 redirect instead of the data feed).
### For the Market
- **Threat Intelligence Ecosystem:** Reinforces the shift away from static, indefinitely-held blocklists toward dynamic, time-sensitive intelligence feeds. It highlights the operational overhead in maintaining public resources and the necessary lifecycle management for cybersecurity data.
## Technical Implications
The core data schema is unchanged, making the migration largely a URL path update (`/domains/` to `/domains/v2/`). The critical technical difference is the **automatic data retention mechanism** in v2. This forces downstream consumers to process *active* data, rather than retaining potentially obsolete entries that might still be present in stagnant v1 lists.
## Strategic Analysis
- **Market Positioning:** CERT Polska maintains its position as a reliable provider of critical, actionable threat intelligence in the European cybersecurity theater.
- **Competitive Advantage:** By enforcing newer, cleaner data standards (short retention window), their list remains highly accurate, offering a marginal advantage in reducing false positives over systems that might rely on older, untended feeds.
- **Challenges:** The primary challenge is ensuring high adoption of the new format before the hard cut-off date, which can be difficult when dealing with diverse, often manually managed, legacy systems consuming public feeds.
## Industry Reactions
- **Analyst Opinions:** Analysts likely view this as a best practice for public threat feed management. Over-retention of blocklist data can decrease efficacy and increase operational load for consumers.
- **Expert Commentary:** Experts would emphasize the necessity of implementing monitoring to ensure the 301 redirects are correctly handled and that the new automated retention rule doesn't create immediate blocking gaps if the migration is rushed.
- **Market Response:** Expect a flurry of configuration updates among Polish ISPs, government bodies, and private organizations utilizing the DWWL in the months leading up to June 2025.
## Future Outlook
- **Predictions and Expectations:** CERT Polska will likely leverage the success of the v2 migration to potentially introduce further intelligence enhancements, perhaps related to categorization or response metadata in future list versions.
- **What to Watch For:** Monitoring the compliance rate among major integrators before the June 2025 deadline will be key to assessing the operational impact of this deprecation.
## For Security Professionals
Security teams must audit all integrations relying on the DWWL URLs immediately and schedule the required configuration update to point to the `/v2/` path before the June 1, 2025, deadline. Furthermore, verify that any existing local automation does not depend on list entries remaining indefinitely, as v2 enforces a strict 6-month TTL (Time-To-Live) on the listed threats.