It has only been a few months since Yahoo announced the largest data breach to date of over of 500 million accounts. Since then, forensics experts have been combing through logs at Yahoo and discovered 1 billion (yes with a B) accounts where compromised in 2013, allegedly by a state sponsored attack that modified web browser cookies to infiltrate the backend of Yahoo and impersonate accounts. This by far is the largest breach ever – stealing everything from passwords to birthdates to unencrypted security questions. It has taken 3 years to identify the incident and it only was identified due to pressure Yahoo received after the last breach. As shocking as it may sound, the malicious activity linked to this breach is now way behind us and the data could be used for present, future, or past attacks. Outside of the humiliation for Yahoo security, the anger of its customers, and the pending deal for Verizon, what can the average person do to ensure that a 3-year-old breach does not come back and haunt them? Here are a few simple but prudent tips:
- Do not re-use passwords for work, home, banks or social media accounts. If one password is compromised (i.e. Yahoo), it can be used at other web sites to compromise you integrity. Use unique passwords for everything and never the same ones for work and home.
- Avoid social media games that ask personal questions. Facebook games and posts that ask you to share what city where you born in and what is your first car was are a dead ringer for common security questions. If you answer them, you potentially are sharing your security questions with everyone. These can be used to reset passwords through common steps like “Forgot Your Password”. If your mail account is compromised too, then this is an easy hack to reset your password to impersonate your account.
- Turn on two factor authentication for signing into websites from new devices. If the web service offers to send you a code via email or even text to validate a new logon, use it. While SMS texting has been proven to be less than secure, and not recommended by security experts, it still provides a better security layer than just a traditional username and password. More complex two factor authentication is always preferred but a simple extra step can stop a hacker from re-using your compromised credentials.
- Vigilance. While financial records are the obvious goal of most attacks, medical records, and other sources of data can be just as valuable. Fraudulent billing, white plastic credit cards, and even phishing attacks can result from compromised data. Keep an eye on all your financial accounts, medical records and bills, and suspicious emails. Once your data is out there, linking it to all important information is trivial and simple symptoms can reveal if you’re are victim of identity theft.
While the Yahoo breach is shocking, and almost feels like old news since it happened again, we need to learn basic steps to prevent this incident from personally affecting consumers and businesses. If we can change our own basic behaviors like re-using passwords and not sharing personal information on social media, we can mitigate the threats this type of travesty has on all of us.
If you have any questions, contact our security experts now. And if you have a Yahoo account, here's the security notice.

Morey J. Haber, Chief Security Officer, BeyondTrust
Morey J. Haber is the Chief Security Officer at BeyondTrust. He has more than 25 years of IT industry experience and has authored four books: Privileged Attack Vectors, Asset Attack Vectors, Identity Attack Vectors, and Cloud Attack Vectors. He is a founding member of the industry group Transparency in Cyber, and in 2020 was elected to the Identity Defined Security Alliance (IDSA) Executive Advisory Board. Morey currently oversees BeyondTrust security and governance for corporate and cloud based solutions and regularly consults for global periodicals and media. He originally joined BeyondTrust in 2012 as a part of the eEye Digital Security acquisition where he served as a Product Owner and Solutions Engineer since 2004. Prior to eEye, he was Beta Development Manager for Computer Associates, Inc. He began his career as Reliability and Maintainability Engineer for a government contractor building flight and training simulators. He earned a Bachelor of Science degree in Electrical Engineering from the State University of New York at Stony Brook.