Describe CVE-2018-1061.
What is CVE-2018-1061?
python before versions 2.7.15, 3.4.9, 3.5.6rc1, 3.6.5rc1 and 3.7.0 is vulnerable to catastrophic backtracking in the difflib.IS_LINE_JUNK method.  An attacker could use this flaw to cause denial of service..