Campaign Monitor Services Under Attack

Australian-based email marketing firm Campaign Monitor was subjected to a prolonged hack-and-spam attack during the last four days. In a post on the official blog, website representative Matthew Patterson admitted that the service was facing a complex and well-planned intrusion from an unknown source.

The attack started last Saturday and continued through Sunday for a few couple of hours, continuing in the days of the next week but not as powerful and sustained as during the weekend. No details about the attack source, whether it's a virus or human attack or what data was stolen are known by Campaign Monitor officials.

They have announced that a vulnerable server containing secure and authentication data was breached and some of the member details stolen. Attackers using some of the stolen account information have deployed a spam campaign using the user's contact lists and some imported addresses.

The amount of traffic generated led to some lag in email-sending operations. Campaign Monitor's tech department responded by blacklisting a series of accounts, in a desperate attempt to stop the outgoing spam. Company officials admitted that some guiltless users that were sending out legitimate email marketing campaigns might have been accidentally placed on the list as well.

Meanwhile, Campaign Monitor has deployed all its technical capabilities to resolve this problem, employing external security, database and hosting experts to help stop and control the attack. All the members whose accounts were hacked in and stolen were informed by email of this incident. Users placed on the blacklist have also been informed, and administrators started to verify each blacklisted account for later clearing.

According to the blog post, the breached server contained financial credit card details, but the data was kept in an encrypted form and is believed to have been secure from the attack.

Campaign Monitor is still handling the after-effects of the attack and looking for its source. Matthew Patterson stated that “This has been a deliberate, planned and complex intrusion and we are still in the process of handling the hacks and the impact.”