Vulnerability Advisory : Halloy has a file transfer path traveral vulnerability with LOW Attack Complexity

Halloy is an IRC application written in Rust. Prior to commit 0f77b2cfc5f822517a256ea5a4b94bad8bfe38b6, the DCC receive flow did not sanitize filenames from incoming `DCC SEND` requests. A remote IRC user could send a filename with path traversal sequences like `../../.ssh/authorized_keys` and the file would be written outside the user's configured `save_directory`. With auto-accept enabled this required zero interaction from the victim. Starting with commit 0f77b2cfc5f822517a256ea5a4b94bad8bfe38b6, all identified code paths sanitize filenames through a shared `sanitize_filename` function.