Password manager LastPass announced a data breach incident yesterday where suspicious activity was identified on its network, and user data has been compromised. LastPass stated that the hackers stole data that included master passwords and other login details, potentially exposing data that has been stored with passwords. More specifically, the announcement refers to “user email addresses, password reminders, server per user salts and authentication hashes.”

It’s not the first time, and certainly not the last time, that cyberattacks have targeted password managers. Last year we wrote about a different type of attack that targeted password managers using a variant of the Citadel Trojan, which targets end-user systems. Since those password managers are installed locally, some have suggested that cloud-based password managers and single sign-on (SSO) solutions might provide an alternative. However, this breach shows that attackers will try to compromise any password manager solution regardless of its architecture, and with a cloud-based password manager, the attackers gain an asymmetric advantage: Instead of one machine yielding credentials for one user, they only have to target a single site to compromise the credentials of thousands, if not millions, of users.

In these days of endless breaches, requiring the use of complex passwords is imperative. Yet for many users, managing different passwords and remembering them is a hassle. In order to minimize the number of passwords to remember, some will reuse the same password. This is a dangerous practice because, if stolen, that single password can provide access to all systems and sites with no separation between personal apps such as Pinterest and corporate systems. Cybercriminals know this, which is why even seemingly innocuous credentials are so valuable to them. There is no shortage of examples of websites that were breached and user credentials stolen: eBay had 150 million passwords stolen; millions of passwords were stolen from LinkedIn; and Yahoo, Adobe and many others join the litany.

As a consequence, it is important to require employees to use different passwords for accessing corporate resources and their personal apps. This can easily be achieved with credential protection platforms that can automatically alert on, and optionally prevent, password reuse by employees.

As for LastPass users, the company says that it is confident that the encryption measures it uses “are sufficient to protect the vast majority of users.” In any case, we recommend that at minimum users change their master passwords. To be on the safe side, it is probably best to change all the passwords contained by LastPass, as well.