Common Causes of Legitimate Websites Being Blocked

  1. Shared IP Addresses:

    • Cause: Many websites share the same IP address, especially in virtual hosting environments. If one website on the shared IP is flagged for malicious activity, other websites on the same IP can also be affected.
    • Example: A legitimate e-commerce site might be blocked because it shares an IP address with a site that was previously flagged for distributing malware.

  2. IP Address History:

    • Cause: An IP address that was previously used by a malicious website can carry over its bad reputation to new websites using the same IP.
    • Example: A new blog might be blocked because its IP address was previously associated with a phishing site.

  3. DNS Anomalies:

    • Cause: Irregularities in DNS records, such as mismatched or rapidly changing DNS entries, can raise suspicion.
    • Example: A legitimate website might be blocked if its DNS records show frequent changes, which can be a tactic used by malicious sites to evade detection.

  4. Reported Malicious Behavior:

    • Cause: User reports and automated systems can flag websites for suspicious behavior, even if the site is legitimate.
    • Example: A legitimate forum might be blocked because users reported it for spam, even though the spam was posted by a few rogue users.

  5. Content Similarity:

    • Cause: Websites with content similar to known malicious sites can be flagged.
    • Example: A legitimate tech blog might be blocked because it uses similar keywords and phrases as a known scam site.

  6. Compromised Websites:

    • Cause: Legitimate websites that have been hacked and used to distribute malware or phishing can be blocked.
    • Example: A small business website might be blocked because it was compromised and used to host a phishing page.

  7. Suspicious Behavior Patterns:

    • Cause: Unusual traffic patterns or behaviors, such as high volumes of traffic from certain regions, can trigger blocks.
    • Example: A legitimate news site might be blocked because it suddenly receives a large amount of traffic from a country known for cyber attacks.

Anecdotes

  • Case of the Shared IP: A small online store was blocked by multiple URL databases because it shared an IP address with a site that was previously flagged for distributing pirated software. The store owner had to contact the hosting provider to get a dedicated IP address and request re-evaluation from the URL databases.

  • DNS Anomaly Incident: A non-profit organization’s website was blocked due to frequent DNS changes. The organization was switching DNS providers to improve performance, but the rapid changes triggered suspicion. They had to provide documentation to the URL database maintainers to explain the changes and get unblocked.

  • Compromised Site Example: A popular blog was blocked after being hacked and used to host a phishing page. The blog owner had to clean up the site, improve security measures, and request a review from the URL databases to get the block lifted.