The Developer Tools feature suffered from XUL injection vulnerability due to improper sanitization of the web page source code. In the worst case this could allow arbitrary code execution when opening a malicious page with the style editor tool.
Name: the Mozilla project
Upstream: Frederik Braun
This issue has been addressed in the following products:
Red Hat Enterprise Linux 7
Red Hat Enterprise Linux 6
Via RHSA-2017:2456 https://access.redhat.com/errata/RHSA-2017:2456