Yahoo Inc Data Breach: 500 Million Users Affected

In July, news started to break about a massive Yahoo Inc data breach. It has taken some time, but the Yahoo Inc data breach has now been confirmed. And it was huge.

The Yahoo Inc data breach beats the massive cyberattack on Heartland Payment Systems in 2009 (130 million records), the LinkedIn cyberattack discovered this summer (117 million records), and the 2011 Sony data breach (100 million records). In fact, the Yahoo Inc data breach is the largest ever reported. More records were stolen in the cyberattack than those three breaches combined. More than 500 million accounts were compromised, according to Yahoo.

Yahoo Inc Data Breach Worse than Initially Thought

The Yahoo Inc data breach came to light when a hacker added a listing to the Darknet marketplace, theRealDeal. The credentials of 280 million account holders were offered for sale by a hacker called ‘Peace’. To anyone who follows Internet security news, the name of the hacker selling the data should be familiar. Peace recently listed the data from the LinkedIn hack for sale.

The 280 million Yahoo records were listed for a paltry $1,800. That payment would buy a cybercriminal names, usernames, easily crackable passwords, backup email addresses, and dates of birth. While the data were listed for sale 2 months ago, Yahoo has only just announced the breach.

After being alerted to the listing, Yahoo initiated an internal investigation. The investigation allegedly did not uncover any evidence to suggest that the claims made by “Peace” were genuine. However, the internal investigation did reveal that someone else had hacked Yahoo’s systems. Yahoo claims the hack was performed by a state-sponsored hacker.

Yahoo issued a statement saying “The investigation has found no evidence that the state-sponsored actor is currently in Yahoo’s network.” While that is undoubtedly good news, the bad news is that access is no longer required because user’s data have already been stolen.

The stolen data include names, email addresses, dates of birth, telephone numbers, security questions and answers, and hashed passwords. According to Yahoo, users’ bank account information and payment card details do not appear to have been stolen. Those credentials were stored in a separate system.

What is most concerning about the Yahoo Inc data breach is not the fact that its systems were compromised, but how it has taken so long for Yahoo to discover the cyberattack. The breach did not occur over the summer. The hack took place in 2014.

The results of the Yahoo Inc data breach investigation will have come as a nasty shock to Verizon. The company agreed to buy Yahoo’s core web business, including Yahoo email, in the summer for $4.8bn. It is possible that Verizon may now be having second thoughts about that deal. Whether the hack will have an impact on the purchase remains to be seen, but for Yahoo the timing could not be much worse.

Yahoo Account Holders Advised to Change Passwords and Security Q&As

Yahoo account holders are unlikely to be concerned about any potential sale of their email accounts to Verizon. They will however be concerned about the sale of their credentials to cybercriminal gangs. Even if the data that were listed for sale by Peace are not genuine, someone somewhere does have their data. Most likely, their data are in the hands of multiple criminals. Those data can – and will – be used in a variety of malicious ways.

Yahoo has now placed a notice on its website alerting users to the breach of their data. Yahoo has also sent out emails to affected users urging them to login to their accounts and change their passwords and security questions. The old security questions and answers have now been invalidated and Yahoo has told users to check their accounts for any suspicious activity, albeit out of “an abundance of caution”.

Fortunately for account holders, the majority of passwords were encrypted with bcrypt – a relatively secure form of encryption. However, that does not mean that the passwords cannot be cracked nor that email account holders are not at risk as a result of the Yahoo Inc data breach.

Yahoo Users at Risk of Phishing Attacks

Cybercriminals may not be able to crack the passwords and gain access to user accounts, but they have all the data they need to conduct phishing campaigns.

Yahoo has already emailed users alerting them to the breach, but the emails contained links that can be used to change passwords and security questions. Any cybercriminal in possession of the stolen data is likely to copy the official emails sent by Yahoo. However, instead of links to Yahoo’s website, the emails will contain links to phishing sites.

Those sites are likely to look exactly the same as the official Yahoo site. However, any user entering a new password or security question, would simply be disclosing that information to the attacker. Emails are also likely to be sent that direct users to websites containing exploit kits. Clicking the links will result in malware and ransomware downloads.

If the criminals behind the attack – or those in possession of the data – do manage to crack the passwords, it is not only Yahoo email accounts that could be compromised. Any individual who has used the same password on other websites faces a high risk of other accounts being compromised. Bank accounts, social media accounts, other email accounts, E-bay and Amazon.com accounts could all be at risk.

The data could also be used for social engineering scams, via email or telephone. Criminals will be looking to obtain the extra data they need to commit identity theft and other types of fraud.

How to Minimize Risk and Protect Yourself

 

  • Never click on any links contained in emails. Even if an email looks official and contains a link to help.yahoo.com or login.yahoo.com, do not click on the links. Instead, login to your account in the usual way by entering the web address directly into your browser and change your password and security questions.
  • Use a strong password containing letters (capitals, and lower case), numbers, and special characters.
  • If you have used the same password for multiple websites, change those passwords immediately. Each website requires a different password. Use a password manager – either a free or paid service – to remember all your passwords.
  • Use Yahoo Account Key, which will eliminate the need for a password altogether
  • Never respond to any email request for personal information
  • Never open any attachments sent via email unless you are certain of their genuineness

HIPAA Guidance on Ransomware Issued by HHS

In response to the massive rise in ransomware attacks on healthcare organizations, the Department of Health and Human Services’ Office for Civil Rights has developed new HIPAA guidance on ransomware for covered entities.

The guidance covers best practices that can be adopted to prevent cybercriminals from installing ransomware, along with helpful advice on how to prepare for ransomware attacks and how to respond when critical files are encrypted by malicious software. Importantly, the new HHS guidance on ransomware also confirms how these security breaches are classified under the Health Insurance Portability and Accountability Act. Many healthcare security professionals feel that HIPAA guidance on ransomware has been long overdue due to the uncertainty about maintaining HIPAA compliance following a ransomware attack. .

HIPAA Guidance on Ransomware Clarifies Attacks ARE Reportable Data Breaches

In the new HIPAA guidance on ransomware, OCR has clarified the reporting requirements for ransomware attacks under HIPAA. Over the past few months, as ransomware attacks on healthcare organizations have soared, there has been much confusion over whether these attacks are classed as security incidents under HIPAA Rules.

It has been argued that since ransomware blindly encrypts files and does not usually involve the attackers actually gaining access to data, the incidents should not be reportable to the HHS. Also, it has been argued that there is no need to issue breach notification letters to patients whose data are temporarily encrypted.

The OCR has now confirmed that ransomware attacks are reportable and require a full breach response, including the mailing of breach notification letters to affected patients and health plan members.

A ransomware attack is considered to be a data breach unless the covered entity can demonstrate that there was only a “low probability that PHI has been compromised.” The OCR considers a breach to have occurred if “unauthorized individuals have taken possession or control of the information.”

How HIPAA Covered Entities Must Respond to Ransomware Attacks

Any HIPAA covered entity that experiences a ransomware attack must orchestrate a full breach response and proceed as they would for a malware attack or if a hacker gained access to PHI.

An accurate and thorough risk assessment must be conducted to determine whether there is any risk to the confidentiality, integrity, or availability of electronic protected health information (ePHI). HIPAA requires the infection to be contained and data must be restored to allow normal operations to continue. Security measures must be implemented to mitigate risks and prevent future attacks.

The Office for Civil Rights must be notified of the breach within 60 days of the discovery of the attack if the breach impacts 500 or more patients, or at the end of the year in the case of a smaller breach of patient records. Breach notification letters must also be mailed to patients within 60 days, in accordance with the HIPAA Breach Notification Rule. A breach notice must also be submitted to the media if the breach impacts 500 or more individuals.

Preparing for a Ransomware Attack

The new HIPAA guidance on ransomware explains that organizations must be prepared to deal with ransomware attacks.

Healthcare organizations should implement cybersecurity protection measures to prevent ransomware attacks, such as installing a robust spam filtering solution such as SpamTitan. Spam filters can prevent the majority of malicious emails from being delivered to end users. Staff members should also be trained on the risk of ransomware and advised how to identify phishing emails and malicious websites.

A risk analysis should be conducted to identify potential cybersecurity vulnerabilities that could be exploited by hackers to install ransomware. Any vulnerabilities that could increase the risk of a ransomware attack being successful should be addressed in a timely fashion.

An emergency operation plan must also be developed that can be immediately put in place upon discovery of a ransomware attack. The new HIPAA guidance on ransomware also states that emergency response plans should be regularly tested to ensure that they are effective.

Ransomware Attacks on Healthcare Organizations Soar

This year has seen an extraordinary number of ransomware attacks on healthcare organizations. In February, ransomware was installed on computers at Hollywood Presbyterian Medical Center in California and a ransom demand of $17,000 was issued. Hollywood Presbyterian Medical Center felt the best course of action to minimize damage was to pay the ransom and obtain the decryption keys to unlock data. On receipt of the funds, the attackers made good on their promise and supplied the keys to unlock the encryption.

However, some organizations have discovered that simply paying a ransom demand does not spell the end of the problem. There have been cases – notably Kansas Heart Hospital – where a ransom has been paid, only for a second ransom demand to be issued. Other companies have paid and not been supplied with working keys. Paying a ransom is no guarantee that data can be decrypted.

The FBI advises against paying ransom demands. Not only is there no guarantee that the attackers will supply working keys, but payment of ransoms only encourages the attackers to continue with their ransomware campaigns. Only by preparing for ransomware attacks can organizations ensure that in the event of ransomware being installed, they will be able to recover their files quickly without giving in to attackers’ demands.

The Ransomware Threat Should Not Be Ignored

The threat to healthcare organizations is severe. Research conducted by anti-phishing company PhishMe showed that in Q1, 2016, 93% of phishing emails contained ransomware. Figures from Symantec Security Response show that on average, 4,000 ransomware attacks have occurred every day since January 1, 2016. A report from security firm Solutionary, shows that in 2016, 88% of ransomware detections were by healthcare organizations.

So far this year, in addition to the attack on Hollywood Presbyterian Medical Center, ransomware attacks have been reported by MedStar Health and DeKalb Health, while Prime Healthcare reported that three of its hospitals – Desert Valley Hospital, Chino Valley Medical Center and Alvarado Hospital Medical Center – were attacked with ransomware. Methodist Hospital in Kentucky, Massachusetts General Hospital, and Yuba Sutter Medical Clinic in California have also reported ransomware attacks this year, to name but a few.

It may not be possible to prevent ransomware attacks, but if healthcare organizations invest in better security protections, the majority of attacks can be prevented. Provided that adequate preparations are made for ransomware attacks, in the event that the malicious software is installed, damage can be limited.

The HIPAA guidance on ransomware can be downloaded from the HHS website.

How to Avoid Email Server Blacklisting

Knowing how to avoid email server blacklisting is vitally important for any organization that relies on email as a channel of communication. The consequences of your email server being blacklisted can be costly, inconvenient, and potentially damaging to your organization´s credibility.

To best understand what email server blacklisting might mean to your organization, it is ideal to have a little knowledge about how email server filters work. Consequently we have divided this post into three sections explaining a little about email server filters, what may cause your email server to be blacklisted, and how to avoid email server blacklisting.

A Little about Email Server Filters

Email server filters do not actually filter your incoming emails at server level. They protect your organization from spam emails and other email-borne threats from the cloud or as a virtual appliance installed between your firewall and your email server. The distinction between the two types of filter is that virtual appliances can be more appropriate for some larger organizations.

Regardless of how they are deployed, email filters effectively work in the same way – using fast front-end tests to detect and reject the majority of spam emails before a deeper analysis is conducted of the email that remains. One of these front-end tests is a comparison of each email against a list of known sources of spam. This list is known as the Realtime Block List or RBL.

If your organization´s IP address appears on this list, all of your emails will be rejected by most email filters until the IP address is removed from the list – something that can take anything from 24 hours to six months to resolve completely. During this time you will have to ask your customers and other contacts to add your email address to a safe list or “whitelist”.

Why Was My Email Server Blacklisted?

There are several reasons why an email address (or IP address) can be blacklisted, and it is important to find out the exact reason(s) before trying to get your organization´s IP address removed from the Realtime Block List. If you fail to identify the cause, and fail to take steps to avoid email server blacklisting in the future, it can be much tougher to get un-blacklisted second time around.

Blacklisting typically occurs for one of several reasons:

  • Your system has been infected with a spambot that has created multiple email accounts within your organization´s domain and is using those accounts to send out spam email.
  • Someone in your organization may have revealed their login credentials and a spammer is using that information to send spam emails from the end-user´s email account.
  • Emails sent innocently from one or more end-user accounts have had a high proportion of spam-related keywords, or have had infected files attached to them.

The last scenario is entirely possible if an end-user has prepared a presentation or spreadsheet on an infected home computer and bought the infected file into the workplace on a flash drive. Most email filters have antivirus software for identifying malware in attachments. If the infected attachment is sent to multiple recipients – and identified by multiple email filters – your organization´s IP address will quickly be blacklisted.

How to Avoid Email Server Blacklisting

Ideally, organizations should be able to avoid email server blacklisting by having robust antivirus protection and educating their end-users about online security. There should also be an email usage policy in place that would avoid email server blacklisting due to inappropriate content or unsafe attachments – even when these events occur inadvertently.

Unfortunately end-users are the weakest link in the security chain, and it only takes one end-user to click on a malicious URL or reveal their login credentials for an organization´s IP address to be blacklisted. In fact, if blacklisting is the worse consequence of a security breach, your organization has got off lightly and should consider itself lucky that the consequences were not far more serious.

Consequently, the best way how to avoid email server blacklisting is with an email filter that has malicious URL blocking to prevent end-users visiting malware-infested websites, with phishing protection to reject emails directing an end-user to fake website, and outbound scanning to identify potential spam and infections contained in – or attached to – outgoing emails.

Avoid Email Server Blacklisting with SpamTitan

Not all email filtering solutions have mechanisms to avoid email server blacklisting. However, SpamTitan has taken these factors into account in the design of SpamTitan Cloud and SpamTitan Gateway. Both of our solutions for email filtering use “URIBL” and “SURBL” protocols to compare links contained within inbound emails and their attachments against a global blacklist of known malicious and phishing sites.

The same protocols – along with several other mechanisms – are used in the scanning of outbound mail to ensure it is clear of viruses and could not be interpreted as having spammy content. Outbound scanning would also identify spam emails originating from a spambot or a compromised email account in order to prevent it from being sent and avoid email server blacklisting.

Naturally, you do not want your end-users to be under the impression that their emails have been sent when they are caught by the outbound filter. So SpamTitan Cloud and SpamTitan Gateway have comprehensive reporting features that advise of any problems in order that the problems can be rectified quickly and effectively – certainly more quickly than trying to get your organization´s IP address removed from a Realtime Block List.