CVE-2026-5766: Django has an Improper Handling of Length Parameter Inconsistency

An issue was discovered in 6.0 before 6.0.5 and 5.2 before 5.2.14. ASGI requests with a missing or understated Content-Length header can bypass the FILE_UPLOAD_MAX_MEMORY_SIZE limit, potentially loading large files into memory and causing service degradation.

As a reminder, Django expects a limit to be configured at the web server level rather than solely relying on FILE_UPLOAD_MAX_MEMORY_SIZE. Earlier, unsupported Django series (such as 5.0.x, 4.1.x, and 3.2.x) were not evaluated and may also be affected.

Django thanks Kyle Agronick for reporting this issue.