Vulnerability · Published Apr 7, 2026 · Assigned by DSF
CVE-2026-33033Potential denial-of-service vulnerability in MultiPartParser via base64-encoded file upload
Medium 6.5
In plain English
A medium-severity security flaw in Django from djangoproject. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.9% (higher than 60% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Official description
An issue was discovered in 6.0 before 6.0.4, 5.2 before 5.2.13, and 4.2 before 4.2.30. `MultiPartParser` allows remote attackers to degrade performance by submitting multipart uploads with `Content-Transfer-Encoding: base64` including excessive whitespace. 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 Seokchan Yoon for reporting this issue.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.23 | py3-django | 4.2.30-r0 | ALPINE-CVE-2026-33033 |
| Alpine:v3.24 | py3-django | 5.2.13-r0 | ALPINE-CVE-2026-33033 |
| Debian:12 | python-django | no fix listed | DEBIAN-CVE-2026-33033 |
| Debian:13 | python-django | no fix listed | DEBIAN-CVE-2026-33033 |
| Debian:14 | python-django | 3:4.2.30-1 | DEBIAN-CVE-2026-33033 |
| PyPI | django | 4.2.30, 5.2.13, 6.0.4 | PYSEC-2026-48 |
| PyPI | django | 6.0.4 | GHSA-5mf9-h53q-7mhq |
| PyPI | django | 4.2.30 | GHSA-5mf9-h53q-7mhq |
| PyPI | django | 5.2.13 | GHSA-5mf9-h53q-7mhq |
| Ubuntu:22.04:LTS | python-django | 2:3.2.12-2ubuntu1.26 | USN-8154-1 |
| Ubuntu:22.04:LTS | python-django | 2:3.2.12-2ubuntu1.26 | UBUNTU-CVE-2026-33033 |
| Ubuntu:24.04:LTS | python-django | 3:4.2.11-1ubuntu1.15 | UBUNTU-CVE-2026-33033 |
| Ubuntu:24.04:LTS | python-django | 3:4.2.11-1ubuntu1.15 | USN-8154-1 |
| Ubuntu:25.10 | python-django | 3:5.2.4-1ubuntu2.4 | USN-8154-1 |
| Ubuntu:25.10 | python-django | 3:5.2.4-1ubuntu2.4 | UBUNTU-CVE-2026-33033 |
| Ubuntu:26.04:LTS | python-django | 3:5.2.9-0ubuntu4 | UBUNTU-CVE-2026-33033 |
| Ubuntu:26.10 | python-django | 3:5.2.9-0ubuntu4 | UBUNTU-CVE-2026-33033 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| djangoproject | Django | 6.0 – before 6.0.45.2 – before 5.2.134.2 – before 4.2.30 |
Weakness: CWE-407 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
References
- Django security archive vendor-advisory
- Django releases announcements mailing-list
- Django security releases issued: 6.0.4, 5.2.13, and 4.2.30 vendor-advisory