git-fastclone before 1.0.1 permits arbitrary shell command execution from .gitmodules. If an attacker can instruct a user to run a recursive clone from a repository they control, they can get a client to run an arbitrary shell command. Alternately, if an attacker can MITM an unencrypted git clone, they could exploit this. The ext command will be run if the repository is recursively cloned or if submodules are updated. This attack works when cloning both local and remote repositories.
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.
| Link | Tags |
|---|---|
| https://hackerone.com/reports/104465 | third party advisory exploit |
| http://www.securityfocus.com/bid/81433 | third party advisory vdb entry |
| https://github.com/square/git-fastclone/pull/2 | patch vendor advisory |