curl: libcurl FTP path normalization flaw allows decoded %2e%2e → CWD .. and directory escape (Path Traversal, CWE-22)

ftpparseurlpath in lib/ftp.c URL-decodes FTP path segments e.g. %2e%2e and then splits the decoded path into components using an ad-hoc loop that skips empty components produced by //. The code does not perform canonical path normalization no stack-based handling of . or ... As a result, encoded...