The ProSap Hotel Leak Means 230,911 Old Passwords Could Still Work

HEROIC analysts identified a database breach connected to ProSap Hotel, a Dutch online platform, dated October 31, 2015. The breach exposed 230,911 records, including usernames, email addresses, IP addresses, and passwords hashed with MD5.

Why the ProSap Hotel Breach Is Dangerous

MD5 hashes are quick to crack with modern tools, which means a large share of these 230,911 passwords can realistically be recovered by anyone motivated to try. If you created an account here years ago and never changed that password elsewhere, it may still be sitting active on an email, shopping, or social account today, waiting to be tried by an attacker.

What Was Exposed in the ProSap Hotel Leak

• Usernames
• Email addresses
• IP addresses
• Passwords, hashed with MD5

Why This Matters

A breach of this size gives attackers a substantial list to run through credential stuffing tools, which automatically test each recovered email and password combination against dozens of other popular services. The longer a password has gone unchanged since 2015, the more likely it has ended up reused somewhere else, and the higher the risk of account takeover.

How Database Breaches Like This Happen

A database breach means an attacker gained direct access to the platform's backend storage and extracted the user table in one operation. The use of MD5 hashing here reflects password security standards that were already outdated in 2015, making the exposed hashes far easier to crack than they would be with a modern algorithm like bcrypt.

Check If You Are Affected

If you ever registered with ProSap Hotel, check your exposure now. HEROIC's free breach scanner checks your email against more than 400 billion compromised records, including this one, in seconds.