CVE-2026-42851: Improper Control of Generation of Code

Kitty is a cross-platform GPU based terminal. In versions prior to 0.47.0, a program able to write bytes to a kitty terminal — a remote SSH peer, a downloaded file viewed with `cat`, a log line, an email body rendered in `less`, an issue body in a TUI, etc. — can cause kitty to execute attacker-supplied Python inside the running kitty process, with the user's full privileges. There is no approval prompt, no remote-control permission requirement, no shell-integration interaction, no clipboard touch, and no editor interaction. Version 0.47.0 fixes the issue.