Werkzeug 0.15.5 Released

written by David Lord on 2019-07-17 in Releases , Security

Werkzeug 0.15.5 has been released, containing bug and security fixes. The changelog lists the changes in detail, which include:

  • SharedDataMiddleware safely handles drive names in paths on Windows.
  • The reloader no longer causes an Exec format error in many common situations.
  • The reloader works around an issue when using the pydev debugger.

Security fix for SharedDataMiddleware on Windows

Prior to 0.15.5, it was possible for a third party to potentially access arbitrary files when the application used SharedDataMiddleware on Windows.

Due to the way Python's os.path.join() function works on Windows, a path segment with a drive name will change the drive of the final path. This was previously addressed in the safe_join() function in Werkzeug 0.12.2, but SharedDataMiddleware used a separate implementation and so was not secured by the previous fix.

SharedDataMiddlware now uses safe_join() when fetching requested files. Projects using SharedDataMiddleware on Windows should update as soon as possible to receive the fix.

Thank you to Emre Övünç and Olivier Dony for responsibly reporting the issue. If you think you have discovered a security issue in Werkzeug or another of the Pallets projects, please email security@palletsprojects.com with details.

Install or Upgrade

Install from PyPI with pip:

pip install -U Werkzeug