Multiple security vulnerabilities were identified in the python-tornado web framework prior to version 6.6.0. These include denial-of-service conditions caused by inefficient handling of HTTP/1.1 chunked transfer encoding and obsolete HTTP header line folding, as well as an open redirect vulnerability in the RedirectHandler URL templates. These issues could allow remote unauthenticated attackers to stall the event loop, consume excessive CPU resources, or perform phishing attacks via crafted redirects. The vulnerabilities are fixed in version 6.6-1.oe2403sp3.