Fixes the following security issues: CVE-2017-17405: Command injection vulnerability in Net::FTP (2.4.3): https://www.ruby-lang.org/en/news/2017/12/14/net-ftp-command-injection-cve-2017-17405/ CVE-2017-17742: HTTP response splitting in WEBrick (2.4.4): https://www.ruby-lang.org/en/news/2018/03/28/http-response-splitting-in-webrick-cve-2017-17742/ CVE-2018-6914: Unintentional file and directory creation with directory traversal in tempfile and tmpdir (2.4.4): https://www.ruby-lang.org/en/news/2018/03/28/unintentional-file-and-directory-creation-with-directory-traversal-cve-2018-6914/ CVE-2018-8777: DoS by large request in WEBrick (2.4.4): https://www.ruby-lang.org/en/news/2018/03/28/large-request-dos-in-webrick-cve-2018-8777/ CVE-2018-8778: Buffer under-read in String#unpack (2.4.4): https://www.ruby-lang.org/en/news/2018/03/28/buffer-under-read-unpack-cve-2018-8778/ CVE-2018-8779: Unintentional socket creation by poisoned NUL byte in UNIXServer and UNIXSocket (2.4.4): https://www.ruby-lang.org/en/news/2018/03/28/poisoned-nul-byte-unixsocket-cve-2018-8779/ CVE-2018-8780: Unintentional directory traversal by poisoned NUL byte in Dir (2.4.4): https://www.ruby-lang.org/en/news/2018/03/28/poisoned-nul-byte-dir-cve-2018-8780/ Multiple vulnerabilities in RubyGems (2.4.4): https://www.ruby-lang.org/en/news/2018/02/17/multiple-vulnerabilities-in-rubygems/ Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
