For text file version control on external drives which are plugged into different computers I need a version control system that is not less secure than usual file system access (e.g., from a Linux operating system).
Popular version control systems such as Git or Mercurial offer hooks that can contain arbitrary code. Unfortunately, if hook executables exist in a version controlled directory, they are executed by default. Through configuration, that could possibly be prevented. But opt-out is always worse than opt-in, when it comes to security. (That is why newly created files on a Linux system are not executable by default.)
Is there any alternative to Git/Mercurial/Fossil/… that can be used for local version control (unlike Subversion which always requires a server) without having to fear arbitrary code execution?