basic-ftp: Incomplete CRLF Injection Protection Allows Arbitrary FTP Command Execution via Credentials and MKD Commands

Summary basic-ftp's CRLF injection protection added in commit 2ecc8e2 for GHSA-chqc-8p9q-pq6q is incomplete. Two code paths bypass the protectWhitespace control character check: 1 the login method directly concatenates user-supplied credentials into USER/PASS FTP commands without any validation,...