If you have a DomainTools account, you should think about changing your password immediately! It seems DomainTools experienced a high volume user email harvesting campaign which abused a flaw in their individual membership email update processes. To the best of their knowledge, no DomainTools customer login and password combinations were compromised by this scripting effort but the campaign appears to have correctly matched a few hundred current or historic DomainTools account email addresses & they have issued the following statement.
"We encourage DomainTools account holders to change their passwords as a precautionary security measure. From our investigation it appears the actor used email addresses from prior well-known breaches and ran those against our email update process."
This campaign resulted in the DomainTools website confirming the existence of a limited number of user email addresses in our membership system. From there, the attacker could conceivably attempt login/password combinations sourced from those prior data dumps such as LinkedIn or Dropbox
Bit niche, but worrying if you have an account with them especially if you use the same password on different sites.
Link to story in 1st post