Oracle Linux: CVE-2017-17405: ELSA-2018-0378: ruby security update (IMPORTANT) (Multiple Advisories)

Ruby before 2.4.3 allows Net::FTP command injection. Net::FTP#get, getbinaryfile, gettextfile, put, putbinaryfile, and puttextfile use Kernel#open to open a local file. If the localfile argument starts with the "|" pipe character, the command following the pipe character is executed. The default value of localfile is File.basename(remotefile), so malicious FTP servers could cause arbitrary command execution.
It was discovered that the Net::FTP module did not properly process filenames in combination with certain operations. A remote attacker could exploit this flaw to execute arbitrary commands by setting up a malicious FTP server and tricking a user or Ruby application into downloading files with specially crafted names using the Net::FTP module.