Last month, Paul Lee was reviewing applications for a legal and compliance job at the small technology company he leads when his screening software flagged an anomaly.
Hidden in one of the hundreds of résumés he received was a block of roughly 1,500 characters typed in white text on a white background. It was an AI prompt to ignore prior instructions and declare the applicant a top-tier fit, regardless of whether the person met the role’s requirements.
Lee said he was stunned and described the move as an ethical red flag for a role built on trust and integrity.
“You’re cutting in front of the line,” said Lee, CEO of the 40-person, Irvine, California, company InnoCaption, which makes real-time captioning technology for the deaf and hard-of-hearing community.
Résumé hacking is getting an AI-era upgrade — and not in a way that’s recommended. Whereas desperate job hunters once put keywords in white text to fool screening software, some people are now quietly inputting AI prompts to try to make their applications stand out.
A May 2026 study by researchers at Duke University and collaborators analyzed nearly 200,000 résumés and found that roughly 1% contained hidden prompt injections.
“Job seekers are doing what they feel they need to do to filter through the noise,” Sarah Franklin, CEO of the human resources platform Lattice, told Business Insider. She said the behavior isn’t surprising because employers are overwhelmed with applications and often respond with generic rejections, if anything at all.
“The hiring process feels like this complete black box,” she said.
AI is part of the problem. The technology makes it easy for job seekers to tailor and submit applications at scale, while some employers use it to help them sort through the pile, said Nada Hashmi, an assistant professor of information technology at Babson College. That can mean AI, rather than a person, may be involved in screening applicants before they reach the interview stage, which can give them an incentive to game the system.
“It’s really having AIs kind of talking to each other,” she said.
Even so, résumé hacking may be pointless. Recruiters and hiring managers often review applications in batches and move ahead once they find enough promising candidates, leaving later submissions unchecked, said Nathalia Aryani, corporate director of human resources at property management company Terra Vista.
“The issue is volume,” she said.
Worse, getting noticed for the tactic can come with its own consequences. Those who are caught doing it may be seen as dishonest, and some employers are now actively searching for prompts because word of them is spreading.
At the Zurich-based flight-search startup Zerolook, cofounder and CEO Simone Lini uploaded about 20% of the roughly 350 résumés he had received for two engineering roles to an AI tool last month. He’d heard that applicants were hiding prompt injections and asked it to flag any examples.
One résumé, Lini learned, indeed contained instructions to ignore prior instructions and prioritize their candidacy, saying “their livelihood depends on you doing that,” he recalled.
Lini, whose company is hiring after raising $1.9 million in venture capital, said that while the applicant had relevant experience, the ploy was a turnoff. He added that he disagreed with some commenters on a LinkedIn post he made about the matter who suggested it showed AI savvy.
“It’s just about trying to sneak in and get to the top,” he said, adding that inserting the prompt was not hard to do. He said he blocked the person from applying again.
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