A security researcher claims to have found a zero-byte exploit file with suspicious naming in what appears to be a Microsoft production build, suggesting either accidental shipping of a test build or something more intentional. The post lacks specifics about which Microsoft product or release is affected, and independent news sources confirm Microsoft's official May 2026 Patch Tuesday had no disclosed zero-days, though separate zero-days were released by a different researcher afterward. Without the specific repository or file details, the claim cannot be independently verified though the researcher's established credibility and high engagement suggest the community takes it seriously.