An issue was discovered in the Multipart Request Parser in Django 3.2 before 3.2.18, 4.0 before 4.0.10, and 4.1 before 4.1.7. Passing certain inputs (e.g., an excessive number of parts) to multipart forms could result in too many open files or memory exhaustion, and provided a potential vector for a denial-of-service attack.
In Django 3.2 before 3.2.17, 4.0 before 4.0.9, and 4.1 before 4.1.6, the parsed values of Accept-Language headers are cached in order to avoid repetitive parsing. This leads to a potential denial-of-service vector via excessive memory usage if the raw value of Accept-Language headers is very large.
In Django 3.2 before 3.2.16, 4.0 before 4.0.8, and 4.1 before 4.1.2, internationalized URLs were subject to a potential denial of service attack via the locale parameter, which is treated as a regular expression.