CLEVELAND, OH — A former software developer who secretly planted a “kill switch” inside his employer’s network—crippling systems and locking out thousands of users worldwide—was sentenced Wednesday to four years in federal prison.
Davis Lu, 55, a Chinese national legally residing in Houston, was convicted earlier this year of causing intentional damage to protected computers after he unleashed malicious code on his former employer, a Beachwood, Ohio-based company. The attack followed a corporate restructuring that slashed Lu’s access and responsibilities, triggering a campaign of digital sabotage.
Federal prosecutors revealed that Lu spent months building a trap inside the company’s systems. His code created infinite loops to crash servers, wiped employee profile files, and included a “kill switch” that locked out all users if his own credentials were ever disabled. That exact scenario played out on Sept. 9, 2019, when Lu was placed on leave and ordered to return his company-issued laptop—instantly activating the hidden code and wreaking havoc across the company’s global operations.
The kill switch, coded under the internal name “IsDLEnabledinAD” — a reference to “Is Davis Lu enabled in Active Directory” — disabled user logins and paralyzed company operations. Prosecutors say the sabotage caused hundreds of thousands of dollars in damages.
Evidence presented at trial showed Lu had researched how to escalate privileges, conceal malicious processes, and delete files to hamper any recovery efforts. He also deleted encrypted data just before turning in his laptop.
The FBI’s Cleveland Field Office led the investigation, which ended with Lu’s conviction and a sentence that also includes three years of supervised release.
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Key Points
- Software developer Davis Lu sentenced to 4 years for sabotaging his former employer’s computer systems
- Lu embedded a kill switch that locked out global users after his credentials were disabled
- Attack caused hundreds of thousands in damage and led to widespread system outages
A software engineer’s hidden sabotage code locked down a global network after his demotion, landing him a four-year federal prison term.
