Anna turns records into undecipherable but unique character strings called one-way hashed data.

FORBES

Aside from the relative ease with which attackers guess passwords, once they have stolen the list of usernames and hashed ( a one-way algorithm used to hide data) passwords, the attacker just checks a dictionary of hashed words against the hashed passwords to find matches.

FORBES: Perhaps Sony should consider strong authentication?

Instead, the investigators said, the data was kept in a hashed form - in other words the telephone numbers were transformed into a short code and stored.

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