In Lib/tarfile.py in Python through 3.8.3, an attacker is able to craft a TAR archive leading to an infinite loop when opened by tarfile.open, because _proc_pax lacks header validation. An issue was discovered in urllib2 in Python 2.x through 2.7.17 and urllib in Python 3.x through 3.8.0. CRLF injection is possible if the attacker controls a url parameter, as demonstrated by the first argument to urllib.request.urlopen with \r\n followed by an HTTP header. This is similar to the CVE-2019-9740 query string issue and the CVE-2019-9947 path string issue. A CRLF injection flaw was discovered in python in the way URLs are handled when doing an HTTP/HTTPS connection . An attacker who can control the url parameter passed to urlopen method in the urllib/urllib2 modules can inject CRLF sequences and HTTP headers by abusing the "host" part of the URL