CVE 2019-19844
Django before 1.11.27, 2.x before 2.2.9, and 3.x before 3.0.1 allows account takeover. A suitably crafted email address (that is equal to an existing user's email address after case transformation of Unicode characters) would allow an attacker to be sent a password reset token for the matched user account. (One mitigation in the new releases is to send password reset tokens only to the registered user email address.)
See the 
CVE page on Mitre.org
for more details.
