A ruby2.1 security update has been released for Debian GNU/Linux 8 LTS to address an unsafe object creation vulnerability in the JSON gem.

DLA 2192-1: ruby2.1 security update

Package : ruby2.1
Version : 2.1.5-2+deb8u10
CVE ID : CVE-2020-10663

The JSON gem through 2.2.0 for Ruby, as used in Ruby 2.1 has an
unsafe object creation vulnerability.
This is quite similar to CVE-2013-0269, but does not rely on poor
garbage-collection behavior within Ruby. Specifically, use of JSON
parsing methods can lead to creation of a malicious object within
the interpreter, with adverse effects that are application-dependent.

For Debian 8 "Jessie", this problem has been fixed in version
2.1.5-2+deb8u10.

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