It has been discovered that Ruby before 2.4.8, 2.5.7 and 2.6.5 is vulnerable to code injection. Shell#[] and its alias Shell#test defined in lib/shell.rb allow code injection if the first argument (aka the “command” argument) is untrusted data. An attacker can exploit this to call an arbitrary Ruby method.
It has been discovered that Ruby before 2.4.8, 2.5.7 and 2.6.5 is vulnerable to code injection. Shell#[] and its alias Shell#test defined in lib/shell.rb allow code injection if the first argument (aka the “command” argument) is untrusted data. An attacker can exploit this to call an arbitrary Ruby method.
https://www.ruby-lang.org/en/news/2019/10/01/code-injection-shell-test-cve-2019-16255/
Note that passing untrusted data to methods of Shell is dangerous in general. Users must never do it. However, we treat this particular case as a vulnerability because the purpose of Shell#[] and Shell#[] is considered file testing.
Vulmon