An attacker with access to a minion key can exploit the 'on demand' pillar functionality with a specially crafted git url which could cause and arbitrary command to be run on the master with the same privileges as the master process.
The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.