PowerShell treats several Unicode smart-quote characters (U+2018, U+2019, U+201A, U+201B) as single-quote delimiters in addition to ASCII apostrophe. When interpolating remote SFTP paths into PowerShell commands, rclone only escapes the ASCII apostrophe, allowing an attacker to craft a filename with smart quotes that closes the path literal and injects arbitrary PowerShell commands executed on the SFTP remote as the victim's SSH account.