Tabby: RCE via `tabby://run` URL Scheme

Tabby (formerly Terminus) is a highly configurable terminal emulator. Prior to 1.0.233, Tabby registers itself as the handler for the tabby:// URL scheme on all platforms. The URL scheme handler supports a run command that directly executes OS commands with no user confirmation, sanitization, or sandboxing. An attacker can craft a malicious link (tabby://run?command=...) and deliver it via a website, email, chat message, or any other medium. When a victim clicks the link, the OS launches Tabby which immediately spawns the specified command as a child process with the user's full privileges. This is a zero-click-after-link-visit RCE vulnerability. This vulnerability is fixed in 1.0.233.