Impact

The patches introduced to fix https://github.com/Pylons/waitress/security/advisories/GHSA-m5ff-3wj3-8ph4 were not complete and still would allow an attacker to smuggle requests/split a HTTP request with invalid data.

This updates the existing CVE with ID: CVE-2019-16789

Patches

Waitress version 1.4.2 has been updated to now validate HTTP headers better to avoid the issue, completely fixing all known issues with whitespace.

Workarounds

There are no work-arounds, upgrading to Waitress 1.4.2 is highly recommended.

References

See https://github.com/Pylons/waitress/security/advisories/GHSA-m5ff-3wj3-8ph4 for more information on the security issue.

For more information

If you have any questions or comments about this advisory:

open an issue at https://github.com/Pylons/waitress/issues (if not sensitive or security related) email the Pylons Security mailing list: pylons-project-security@googlegroups.com (if security related)