samurai
n. A computer hacker hired to legally infiltrate corporate computer systems for legitimate reasons.
Other Forms
Examples
1999
Samurai: ethical hacker for hire; unlike criminal or vandalism-oriented hackers and crackers, true silicon Samurai adhere to rigorous and self-imposed standards of loyalty to employers; often hired to seek out rogue employees within a corporation's technical staff.
—Keith Ferrel, “Tomorrow,net,” Chief Executive, January 01, 1999
1992
The press has associated the word "hacker" in people's mind with the nasty troublemaker who tries to steal secret information from others' computer systems. Certainly there are "dark-side hackers", those who crack into confidential files for criminal or malicious ends. Others — the "samurai" — break into files to steal information for more lawful reasons, perhaps for a lawyer pursuing a privacy-rights case.
—David Rowan, “Doing damage with flamage,” The Guardian, November 20, 1992
1992 (earliest)
The press has associated the word "hacker" in people's mind with the nasty troublemaker who tries to steal secret information from others' computer systems. Certainly there are "dark-side hackers", those who crack into confidential files for criminal or malicious ends. Others — the "samurai" — break into files to steal information for more lawful reasons, perhaps for a lawyer pursuing a privacy-rights case.

But mostly the term "hacker" just means an enthusiastic programmer, who plays with a computer for fun rather than to fulfil a specific task.
—David Rowan, “Lingua Franca,” The Guardian, November 20, 1992
Notes
—Lynda Edwards, “Samurai Hackers,” Rolling Stone, September 19, 1991
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