CVE 2017-14867
Git before 2.10.5, 2.11.x before 2.11.4, 2.12.x before 2.12.5, 2.13.x before 2.13.6, and 2.14.x before 2.14.2 uses unsafe Perl scripts to support subcommands such as cvsserver, which allows attackers to execute arbitrary OS commands via shell metacharacters in a module name. The vulnerable code is reachable via git-shell even without CVS support.
See the 
CVE page on Mitre.org
for more details.
