As of Monday January 23rd, we have received reports of customers experiencing increased spam and ransomware emails arising from form submissions.
Our team is aware and have implemented solutions to drastically decrease the frequency of spam coming through. As a result of these new solutions, we have seen a sustained decrease of spam affecting customers.
To control spam volume, we’ve updated our rate limiting system to detect specific networks and request behaviors that indicate use of bots. In addition to volume mitigations, we have worked to tighten our content mitigation controls such as spam filtering, and spoofed form detection. During implementation, some form submissions may have been temporarily disrupted — which could have resulted in a temporary block on form submissions for some site visitors.
We understand that receiving spam of any kind can cause concern — however, we assure you that the spam emails in question have not compromised your site. We encourage you to avoid engaging with any suspicious content.
As the team continues to push added measures and prevention tactics, we recommend enabling Google reCAPTCHA on your site forms for an additional level of prevention. You can learn more about how to configure this here: Add a reCAPTCHA field | Webflow University 
In efforts to track and improve our spam filtering system, we encourage you to forward any suspicious activity to form-spam-reports@support.webflow.com and avoid clicking any links contained within these emails.
For any customers who may be worried about extra charges due to an increase in form submissions, we have voided all charges for any form submissions at this time. If you or your client have already been charged, you can contact us through support.webflow.com and we will immediately refund any overages.
— The Webflow Team