An issue was discovered in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1. UserAttributeSimilarityValidator incurred significant overhead in evaluating a submitted password that was artificially large in relation to the comparison values. In a situation where access to user registration was unrestricted, this provided a potential vector for a denial-of-service attack.

Affected: Ubuntu:18.04:LTS: python-django, Ubuntu:20.04:LTS: python-django

Chris Bailey discovered that Django incorrectly handled evaluating submitted passwords. A remote attacker could possibly use this issue to consume resources, resulting in a denial of service. (CVE-2021-45115)

Dennis Brinkrolf discovered that Django incorrectly handled the dictsort template filter. A remote attacker could possibly use this issue to obtain sensitive information. (CVE-2021-45116)

Dennis Brinkrolf discovered that Django incorrectly handled certain file names. A remote attacker could possibly use this issue to save files to arbitrary filesystem locations. (CVE-2021-45452)