The present disclosure relates to computer-implemented methods, software, and systems for identifying potential attacks through monitoring of user credential login attempts across a network of websites. One example method includes monitoring login attempts associated with a plurality of websites and identifying a first login attempt at a first website associated with a set of user credentials. In response to determining that the set of user credentials do not correspond to a valid set of credentials, a count value associated with an entry in a failed credential log associated with the user credentials is incremented. If the count threshold associated with a compromised user credential rule is exceeded by the current count value, then the first set of credentials is identified as a set of compromised credentials and at least one protective action is initiated.