Yes. Under the Digital Millennium Copyright Act (DMCA) and similar laws worldwide (EUCD, Copyright Act of Canada), circumventing access controls (Steam’s DRM) is a violation. Using GreenLuna violates the Steam Subscriber Agreement (SSA), specifically Section 1.C: "You may not ... bypass, modify, defeat, or circumvent any of the security features."

: The injector will automatically close any running Steam instances and relaunch them with GreenLuma active. Safety & Verification Detection Risk