CentOS Errata and Security Advisory CESA-2015:2561
Git is a distributed revision control system with a decentralized architecture. As opposed to centralized version control systems with a client-server model, Git ensures that each working copy of a Git repository is an exact copy with complete revision history. This not only allows the user to work on and contribute to projects without the need to have permission to push the changes to their official repositories, but also makes it possible for the user to work with no network connection.
A flaw was found in the way the git-remote-ext helper processed certain URLs. If a user had Git configured to automatically clone submodules from untrusted repositories, an attacker could inject commands into the URL of a submodule, allowing them to execute arbitrary code on the user's system. (BZ#1269794)
All git users are advised to upgrade to these updated packages, which contain a backported patch to correct this issue.
Merged security bulletin from advisories: http://lists.centos.org/pipermail/centos-cr-announce/2015-December/002733.html
Affected packages: emacs-git emacs-git-el git git-all git-bzr git-cvs git-daemon git-email git-gui git-hg git-p4 git-svn gitk gitweb perl-Git perl-Git-SVN
Upstream details at: https://rhn.redhat.com/errata/RHSA-2015-2561.html