A ruby2.1 security update has been released for Debian GNU/Linux 8 LTS

Package : ruby2.1
Version : 2.1.5-2+deb8u8
CVE ID : CVE-2019-15845 CVE-2019-16201 CVE-2019-16254
CVE-2019-16255

Several flaws have been found in ruby2.1, an interpreter of an
object-oriented scripting language.

CVE-2019-15845
Path matching might pass in File.fnmatch and File.fnmatch? due
to a NUL character injection.

CVE-2019-16201
A loop caused by a wrong regular expression could lead to a denial
of service of a WEBrick service.

CVE-2019-16254
This is the same issue as CVE-2017-17742, whose fix was not complete.

CVE-2019-16255
Giving untrusted data to the first argument of Shell#[] and
Shell#test might lead to a code injection vulnerability.

For Debian 8 "Jessie", these problems have been fixed in version
2.1.5-2+deb8u8.

We recommend that you upgrade your ruby2.1 packages.

Further information about Debian LTS security advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://wiki.debian.org/LTS