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- Blacklisted on any of the blacklists in the "Possible IP List Bombing" email; OR
- A combination of the following:
- High spam rate on Cleantalk – anything above 2-3% should raise a red flag.
- IP is located in problematic regions (ie, SE Asia, China, Russia, Eastern Europe)
- High discrepancy btwn between unique emails email addresses and unique signups/attempts
- Apparent but unmarked bulk uploads in SUA2 (eg, dozens of signups within a second, patterns in uploads, etc)
Here's a sample of a domain that was shown as NOT blacklisted in the email, but could be added to our block list. However, it turned out this particular IP was confirmed to be legit by a client, so tread carefully if the IP is not blacklisted:
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The following addresses have been positively ID'd as legit sources of signups (to be whitelisted):
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