Arch Linux: Information disclosure (CVE-2017-8817)

A read out of bounds flaw has been found in the FTP wildcard function of libcurl >= 7.21.0 and < 7.57.0. libcurl's FTP wildcard matching feature, which is enabled with the `CURLOPT_WILDCARDMATCH` option can use a built-in wildcard function or a user provided one. The built-in wildcard function has a flaw that makes it not detect the end of the pattern string if it ends with an open bracket (`[`) but instead it will continue reading the heap beyond the end of the URL buffer that holds the wildcard.
For applications that use HTTP(S) URLs, allow libcurl to handle redirects and have FTP wildcards enabled, this flaw can be triggered by malicious servers that can redirect clients to a URL using such a wildcard pattern.