The vulnerability arises from kitty's color_control() function in kitty/window.py, which responds to queries for unrecognized field names by including the field name in its reply. This reply is then written to the pseudoterminal master by write_escape_code_to_child() in kitty/screen.c without neutralizing shell-special characters, allowing the injected content to be interpreted as shell commands. Although the payload is restricted to printable ASCII and delimiters like ';' and '=' are consumed, other printable characters remain, enabling command composition. Additionally, a newline character is available from handle_remote_ssh() in kitty/window.py, which writes SSH data to the pseudoterminal master before credential verification, facilitating command injection. This results in execution of attacker-chosen commands with the user's privileges.

Successful exploitation allows an attacker to execute arbitrary shell commands with the privileges of the user running the kitty terminal emulator. This can lead to full compromise of the user's environment, data theft, or further system compromise. The vulnerability is rated critical with a CVSS 4.0 score of 9.3, reflecting high attack complexity but severe impact on confidentiality, integrity, and availability.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, users should avoid running untrusted programs that write to the terminal or disable features that process escape sequences if possible. Monitor vendor channels for updates and apply patches promptly once released.