Potential denial-of-service vulnerability in ASGI requests via file upload limit bypass
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 would like to thank Kyle Agronick for reporting this issue.
02 / AFFECTED SOFTWARE
Affected packages
19 explicit affected versions
19 explicit affected versions
19 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
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 would like to thank Kyle Agronick for reporting this issue.
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 would like to thank Kyle Agronick for reporting this issue.
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.
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 would like to thank Kyle Agronick for reporting this issue.
05 / REFERENCES
Further evidence
- https://docs.djangoproject.com/en/dev/releases/security/
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/5xxx/CVE-2026-5766.json
- https://github.com/django/django/
- https://groups.google.com/g/django-announce
- https://nvd.nist.gov/vuln/detail/CVE-2026-5766
- https://pypi.org/project/Django/
- https://www.djangoproject.com/weblog/2026/may/05/security-releases/
- https://github.com/advisories/GHSA-w26r-rmm8-9c29
- https://docs.djangoproject.com/en/dev/releases/security
- https://github.com/django/django
- https://github.com/pypa/advisory-database/tree/main/vulns/django/PYSEC-2026-54.yaml
- https://www.djangoproject.com/weblog/2026/may/05/security-releases