gunicorn version 19.4.5 contains a CWE-113: Improper Neutralization of CRLF Sequences in HTTP Headers vulnerability in process_headers function in gunicorn/http/wsgi.py that can result in an attacker causing the server to return arbitrary HTTP headers. This vulnerability appears to have been fixed in 19.5.0. https://nvd.nist.gov/vuln/detail/CVE-2018-1000164