Online forms everywhere are experiencing fraudulent sign-up attacks. When a website form lacks human verification, such as CAPTCHA, it becomes susceptible. This includes Constant Contact's sign-up forms that are embedded on websites.
Fraudulent sign-ups are the work of automated computer programs finding unprotected sign-up forms on the web. Once a form is located, the program will start submitting fictitious email addresses into the form. The result is a flood of unsolicited mail arriving in the victim's inbox. Fraudulent sign-ups can impact Constant Contact's sending reputation since some of these “fictitious” email addresses belong to real people who didn't ask for mail.
We have a process in place to help identify fraudulent sign-up behavior, and prevent fictitious names from getting added to your account. You should also take steps to protect your sign-up form from these attacks.
When email addresses are added to your account, we check to see if they're suspicious. Any email suspected of being fictitious is placed directly into the "Temporary Hold - Do Not Email" status.
If you have contacts in the "Temporary Hold - Do Not Email" status, please leave them there. During these kinds of attacks, the same email addresses are getting reused over and over again. Another attempt could be made to add them to your list. Leaving them in your account prevents them from getting added again. Remember, you won't be charged for keeping these contacts in your account.
Prevention, of course, is the best medicine. Here are ways to prevent fraudulent sign-ups:
We automatically turn on rate limiting and CAPTCHA. These limit the number of signups per hour, and require each signup to verify that they're human. Here is what else you can do if you've been a victim of an attack:
We are continuously adjusting our detection methods to prevent fictitious addresses from being added to your list, but some may slip through. Please remain vigilant and watch for unexpected behavior. If you need help identifying or removing fictitious emails from your contact list, please call support.
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