Vulnerabilities

OnionShare is an open source tool that lets you securely and anonymously share files, host websites, and chat with friends using the Tor network. In affected versions the receive mode limits concurrent uploads to 100 per second and blocks other uploads in the same second, which can be triggered by a simple script. An adversary with access to the receive mode can block file upload for others. There is no way to block this attack in public mode due to the anonymity properties of the tor network.

OnionShare 2.3 before 2.4 allows remote unauthenticated attackers to upload files on a non-public node when using the --receive functionality.

The debug_mode function in web/web.py in OnionShare through 1.3.1, when --debug is enabled, uses the /tmp/onionshare_server.log pathname for logging, which might allow local users to overwrite files or obtain sensitive information by using this pathname.

hs.py in OnionShare before 0.9.1 allows local users to modify the hiddenservice by pre-creating the /tmp/onionshare directory.