git-shell in git before 2.4.12, 2.5.x before 2.5.6, 2.6.x before 2.6.7, 2.7.x before 2.7.5, 2.8.x before 2.8.5, 2.9.x before 2.9.4, 2.10.x before 2.10.3, 2.11.x before 2.11.2, and 2.12.x before 2.12.3 might allow remote authenticated users to gain privileges via a repository name that starts with a - (dash) character.
https://security.gentoo.org/glsa/201706-04
https://kernel.googlesource.com/pub/scm/git/git/+/3ec804490a265f4c418a321428c12f3f18b7eff5
https://insinuator.net/2017/05/git-shell-bypass-by-abusing-less-cve-2017-8386/
https://access.redhat.com/errata/RHSA-2017:2491
https://access.redhat.com/errata/RHSA-2017:2004
http://www.ubuntu.com/usn/USN-3287-1
http://www.securitytracker.com/id/1038479
http://www.securityfocus.com/bid/98409
http://www.debian.org/security/2017/dsa-3848
http://public-inbox.org/git/xmqq8tm5ziat.fsf%40gitster.mtv.corp.google.com/
http://lists.opensuse.org/opensuse-updates/2017-05/msg00090.html