The itch.io sandbox
The itch.io sandbox tries to prevent several typical attacks a malicious game could run on a computer.
For example, the sandbox will:
- Limit what files a process can read
- Limit what files a process can write to
- On Linux, be more permissive about writes, but redirect them to a safe, per-game folder
- On Windows, run games as a different, less-privileged user
Attacks that the itch.io sandbox try to prevent include:
Stealing your itch.io credentials
This is especially important if you're a developer. Someone stealing your butler API key could push a malicious build of your game to all your players.
Stealing your browser cookies / saved passwords
This affects everyone. See pycookiecheat for an example of how easy it is to decrypt Chrome's cookies.
Stealing saved passwords is especially scary as it can happen no matter how secure the servers are, see the 2016 twitter leak.
It shouldn't be possible to escape the sandbox by forking/spawning/execing.
The sandbox makes no attempts to protect against:
- The user collaborating in being attacked (giving out their password, running untrusted software, etc.)
- Vulnerabilities in graphics drivers (see WebGL security history)
It's not the answer to everything, but running games via the sandbox safer than not doing so.
For implementation details, please refer to the following platform-specific pages: