A major Children’s Mercy Hospital phishing attack has highlighted the importance of implementing effective spam filtering controls and the need to provide security awareness training to end users.
Phishing is a method of fraudulently obtaining sensitive information through deception. While attacks can occur over the telephone, via social media sites, or through text messages and chat platforms, the most common attack vector is email.
Convincing emails are sent to end users urging them to open an email attachment or to click on a malicious link. Attachments are used to install malware, either directly through malware attached to the email, or more commonly, using macros or other malicious code in documents which download scripts that in turn download the malicious payload.
In the case of embedded hyperlinks in emails, they typically direct an end user to a website that asks them to login. The website could ask for their email credentials, appear to be a Google login box, Dropbox login page, or other file sharing platform. Disclosing login credentials on that webpage sends the information to the attackers. These login pages are convincing. They look exactly like the sites that they are spoofing.
That was the case with the Children’s Mercy Hospital phishing attack. The Kansas City, MO, hospital received several phishing emails which directed employees to fake login pages on criminally-controlled websites.
The phishing attack occurred on or shortly before December 2, 2017. On Dec 2, Children’s Mercy’s security team identified authorized access to two employees’ email accounts. Access to the accounts was blocked the same day and the passwords were reset. Two weeks later, on December 15 and Dec 16, two further email accounts were accessed by unauthorized individuals. Again, unauthorized access was detected and blocked the same day. A fifth email account was accessed on January 3, 2018 with access blocked the following day.
The prompt action in response to the Children’s Mercy phishing attack limited the potential for those email accounts to be abused. When criminals gain access to email accounts they often use them to send further phishing emails. Since those emails come from a legitimate email account, the recipients of the messages sent from that account are more likely to open the emails as they come from a trusted source. That is why business email compromise scams are so effective – because employees trust the sender of the email and take action as requested in the belief that they are genuine communications.
In the case of the Children’s Mercy phishing attack, the criminals acted quickly. Following a forensic investigation into the attacks, Children’s Mercy discovered on January 19, 2018, that even though access to the accounts was promptly blocked, the attackers had successfully downloaded the mailboxes of four of the five employees. The messages contained a wide range of protected health information (PHI) of 63,049 patients.
The PHI included information such as name, gender, age, height, weight, BMI score, procedure dates, admission dates, discharge dates, diagnosis and procedure codes, diagnoses, health conditions, treatment information, contact details, and demographic information.
While Social Security numbers, insurance information, and financial data were not obtained – information most typically required to commit fraud – such detailed information on patients could be used in impersonation attacks on the patients. It would be quite easy for the attackers to pretend they were from the hospital and convince patients to provide their insurance information for example, which could then be used for medical identity fraud.
Due to the scale of the attack and number of emails in the compromised accounts, it has taken a considerable time to identify the individuals affected. The Kansas City Star reports that some patients are only just being notified.
In response, the hospital implemented 2-factor authentication and other technical controls to prevent further attacks.
2-factor authentication is an important security measure that provides protection after a phishing attack has occurred. If login credentials are supplied, but the location or the device used to access the account is unfamiliar, an additional method of authentication is required before access to the account is granted – a code sent to a mobile phone for example.
Two of the most effective security controls to prevent credential theft via phishing are spam filters and security awareness training.
An advanced spam filter is an essential security measure to block phishing attacks. The changing tactics of cybercriminals means no spam filtering solution will be able to block every single phishing email, although SpamTitan, a highly effective spam filtering solution with advanced anti-phishing protections, blocks more than 99.97% of spam and malicious emails to ensure they do not arrive in end users’ inboxes.
Security awareness training helps to prevent employees from clicking on the small percentage of messages that get past perimeter defenses. Employees need to be trained to give them the skills to identify phishing attempts and report them to their security teams. An ongoing training program, with phishing simulation exercises, will help to condition employees to recognize threats and respond appropriately. Over time, phishing email detection skills will improve considerably.
An effective training program can limit the number of employees that respond to phishing attacks, either preventing the attackers from gaining access to email accounts or severely limiting the number of employees who respond and disclose their credentials.
The Children’s Mercy phishing attack is one of many such attacks on healthcare organizations and businesses, and as those attacks increase and more data is obtained by criminals, implementing advanced phishing protections has never been more important.
For further information on email security controls that can prevent phishing attacks, contact the TitanHQ team today and enquire about SpamTitan.