Improper Access Control vulnerability in the com.redhat.lightspeed.history service of the Lightspeed platform. The issue stems from a lack of proper authorization checks in the methods handling user history, allowing any local user to inject, retrieve, or delete the chat history of other users. An attacker can craft and insert a command such as sudo rm -rf / into another user's chat history, relying on trust in past prompts to trigger harmful command execution. This flaw can be exploited without authentication, user interaction, or elevated privileges, affecting all users on the shared system.