Redmine before 3.2.9 3.3.x before 3.3.6 and 3.4.x before 3.4.4 does not block the --config and --debugger flags to the Mercurial hg program which allows remote attackers to execute arbitrary commands (through the Mercurial adapter) via vectors involving a branch whose name begins with a --config= or --debugger= substring a related issue to CVE-2017-17536.