Under Armour has experienced a massive MyFitnessPal data breach that has resulted in the personal information of 150 million users being accessed and stolen by a hacker.

The data relates to users of the mobile MyFitnessPal app and the web version of the fitness and health tracking platform. The types of data stolen in the MyFitnessPal data breach include hashed usernames, passwords and email addresses.

While payment card data is held by Under Armour, the information is processed and stored separately and was unaffected. Other highly sensitive information typically used for identity theft and fraud such as Social Security numbers was not obtained by the attacker.

The MyFitnessPal data breach is notable for the sheer volume of data obtained and is the largest data breach to be detected this year; however, the theft of hashed data would not normally pose an immediate risk to users. That is certainly the case for the passwords, which were hashed using bcrypt – a particularly strong hashing algorithm. However, usernames and passwords were only hashed using the SHA-1 hashing function, which does not offer the same level of protection. It is possible to decode SHA-1 hashed data, which means the information could potentially be accessed by the attacker.

Further, the attacker has had the data for some time. Under Armour became aware of the breach on March 25, 2018, but the attack took place more than a month before it was detected – some six weeks before the announcement about the data breach was made.

Given the method used to protect the usernames and passwords, the data can be considered accessible and it is almost certain the person or persons responsible for the attack will attempt to monetize the data. If the attacker cannot personally decrypt the data, it is certain that the data will be some to someone who can.

While it is possible that the bcrypt-encrypted passwords can be decoded, it is unlikely that decryption will be attempted. To do so would take a considerable amount of time and effort. Further, Under Armour is notifying affected users and is encouraging them to change their passwords as a precaution to ensure accounts cannot be accessed.

While MyFitnessPal accounts may remain secure, that does not mean that users of MyFitnessPal will be unaffected by the breach. The attacker – or current holders of the data – will no doubt use the 150 million email addresses and usernames for phishing campaigns.

Under Armour started notifying affected users four days following the MyFitnessPal data breach. Any user affected should login and change their password as a precaution to prevent their account from being accessed. Users also need to be alert to the risk from phishing.

Phishing campaigns related to the MyFitnessPal data breach can be expected although the attackers will likely develop a variety of phishing emails to target breach victims.

An incident of the scale of the MyFitnessPal data breach also poses a risk to businesses. If an employee was to respond to a phishing campaign, it is possible that they could download malware onto their work device – an action that could result in the business network being compromised.

Attacks on this scale are becoming far more common, and with huge volumes of email addresses now being used for phishing campaigns, advanced spam filtering solutions for businesses are now a necessity.

If you have yet to implement a spam filter, are unhappy with your current provider and the detection/false positive rate, contact TitanHQ to find out about SpamTitan – The leading anti-spam software for enterprises and SMBs.