My website recently encountered a card testing attack which resulted in the exploitation of my WordPress admin login and FTP account. Unfortunately, since the attack, I have been experiencing issues with email deliverability. Specifically, no emails sent from wordpress@mysite.com are getting through to Gmail accounts, and delivery to other webmail providers is sporadic. I am unable to send password change requests and have confirmed that the problem persists even after testing the site with an SMTP plugin.
My email provider is Google Workspace, and my hosting company is unable to offer any assistance since the issue appears to be with my website, and none of the DNS records were altered. I am at a loss as to what could be causing this problem and am seeking further clarification and guidance on how to resolve this issue.
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It seems that there may be some confusion between us regarding the issue at hand. Allow me to clarify and ensure that we are on the same page.
Based on your original post, it appears that you are experiencing problems with emails that are being sent from your WordPress site (specifically from wordpress@example.com) to Gmail accounts. I wanted to understand which tool on your website is responsible for sending these emails, which may either be your hosting server or an SMTP plugin used to connect to an external SMTP server, such as Google Workspace or a transactional email service provider’s API.
I must emphasize that there is no direct integration between WordPress and Google Workspace. Therefore, if you never previously installed or used an SMTP plugin and your website successfully sent emails, then your hosting server would likely be responsible for sending the emails. Nonetheless, the recommended and quickest resolution would be to switch to using a Google Workspace account (via an SMTP plugin) to send the emails.
Moreover, I suggest that you check whether your domain name has been blacklisted in any blacklist databases and work to have it removed if necessary. You may use this tool: https://mxtoolbox.com/blacklists.aspx.
Thank you for providing this additional information.
It seems that an SMTP plugin was not in use with Google servers since the developer built the site in 2017, and no issues with email deliverability had been noticed until now. However, upon checking the “mail” folder in cPanel, you found numerous files in the “cur” folder showing that some messages from the website were not being delivered to your Gmail account, though some did get through. This suggests that emails from wordpress@example.com being sent to info@example.com were going through without any problem.
You also mentioned that the domain is now listed on one blacklist. This might indicate that the domain is being used for spoofing and sending fraudulent emails. To resolve this, you should identify the source of the issue and take immediate steps to mitigate it. This may include checking your website and server for any malware or vulnerabilities that could be exploited by attackers. Additionally, you may contact the blacklist provider and follow their guidelines to remove your domain from the blacklist.
I hope this helps, and please let me know if you have further questions.