Worked example: reading a sign-in log
Overnight, a company’s sign-in portal logged 1,900 failed attempts from one external address. Each of about 950 usernames was tried exactly twice, once with Winter2026! and once with Welcome1, about an hour apart. No accounts locked out and no attempt succeeded. Which of the following is MOST likely occurring?
Pick an answer to see why each option is right or wrong.
Takeaway: count guesses per account, not total failures. Few passwords across many accounts is spraying; many guesses at one account is brute force. Source: MITRE ATT&CK T1110.003, Password Spraying