All Quidd users are advised to change their passwords as soon as possible. Using a password manager helps create strong, unique passwords for every site or service without reusing the same password for every account. According to Risk Based Security who found the dump, many professional email domains were included in the breach. Registering for online services using corporate email accounts is highly discouraged and should be avoided whenever possible. Criminals can use passwords associated with corporate email addresses from breaches of third-party sites to attempt to break into employee accounts (such as Office 365 or other corporate email accounts) if the same or similar password is used. Using multi-factor authentication (MFA) to protect corporate account remote access is an important defense against this type of attack. Breaches like this one that include email addresses also increase potential for spam or targeted phishing attacks.

Sources: https://www.zdnet.com/article/account-details-for-4-million-quidd-users-shared-on-hacking-forum/

Nearly 4 Million Quidd User Credentials Stolen and Shared on Hacking Forum