medium 6.5

CVE-2026-33033 json

Potential denial-of-service vulnerability in MultiPartParser via base64-encoded file upload

published 2026-04-07 7 mo ago modified 2026-10-26 13 d ago also BIT-django-2026-33033 , EUVD-2026-19646 , GHSA-5mf9-h53q-7mhq , PYSEC-2026-48

cvss: 6.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.9%; EPSS 0.9% chance of exploitation in 30 days, percentile 60%
public exploits: 0; none known

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.

Patch / fix

fixed in 3 distros 4 links 2

pypi django 4.2.30, 5.2.13, 6.0.4
bitnami django 4.2.30, 5.2.13, 6.0.4
djangoproject Django 4.2.30, 5.2.13, 6.0.4

debian ubuntu opensuse alpine

python-django Debian 14 3:4.2.30-1

debian advisories DEBIAN-CVE-2026-33033

python-django Ubuntu 22.04 LTS 2:3.2.12-2ubuntu1.26
python-django Ubuntu 24.04 LTS 3:4.2.11-1ubuntu1.15
python-django Ubuntu 25.10 3:5.2.4-1ubuntu2.4
python-django Ubuntu 26.10, Ubuntu 26.04 LTS 3:5.2.9-0ubuntu4
python-django Ubuntu Pro 14.04 LTS 1.6.11-0ubuntu1.3+esm11
python-django Ubuntu Pro 16.04 LTS 1.8.7-1ubuntu5.15+esm12
python-django Ubuntu Pro 18.04 LTS 1:1.11.11-1ubuntu1.21+esm15
python-django Ubuntu Pro 20.04 LTS 2:2.2.12-1ubuntu0.29+esm8

ubuntu advisories UBUNTU-CVE-2026-33033

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

python-Django5 openSUSE Tumbleweed 5.2.16-1.1
python-Django openSUSE Tumbleweed 5.2.13-1.1
python-Django openSUSE Leap 16.0 5.2.4-bp160.7.1
python-Django4 openSUSE Tumbleweed 4.2.30-1.1
python-Django6 openSUSE Tumbleweed 6.0.4-1.1

opensuse advisories openSUSE-SU-2026:11270-1 openSUSE-SU-2026:10567-1 openSUSE-SU-2026:20578-1 openSUSE-SU-2026:10516-1 openSUSE-SU-2026:10517-1

py3-django Alpine 3.23 4.2.30-r0
py3-django Alpine 3.24 5.2.13-r0

alpine advisories ALPINE-CVE-2026-33033

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

docs.djangoproject.com/en/dev/releases/security/ advisory
djangoproject.com/weblog/2026/apr/07/security-releases/ advisory

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-33033 updated 2026-11-07 cvss 5.3

Django: Django: Performance degradation via excessive whitespace in multipart uploads

Red Hat Ansible Automation Platform 2 automation-controller, redhat-user-workloads/es-team-tenant/automation-reports, ansible-automation-platform-24/lightspeed-rhel8-operator, ansible-automation-platform-26/lightspeed-rhel9-operator, redhat-user-workloads/ansible-tenant/ansible-automation-platform-26/hub-rhel9, redhat-user-workloads/ansible-tenant/ansible-automation-platform-26/gateway-rhel9, +3 more Red Hat Discovery 2 redhat-user-workloads/discovery-tenant/discovery/discovery-server Red Hat Satellite 6 redhat-user-workloads/insights-management-tenant/satellite-iop/iop-advisor-backend-sat-6-18
affected: workaround, no fix available “Fix deferred”
Red Hat Ansible Automation Platform 2 ansible-automation-platform-26/hub-rhel9, ansible-automation-platform-27/hub-rhel9, ansible-automation-platform-26/gateway-rhel9, ansible-automation-platform-27/gateway-rhel9, ansible-automation-platform-24/lightspeed-rhel8, ansible-automation-platform-25/lightspeed-rhel8, +10 more Red Hat Discovery 2 discovery/discovery-server-rhel9 Red Hat Satellite 6 satellite/iop-advisor-backend-rhel9 Red Hat Self-service automation portal 2 ansible-automation-platform/bootc-automation-portal-rhel9
under investigation

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 7 mo ago (2026-04-07)

Exploit prediction

0.91% chance of exploitation in the next 30 days, higher than 60% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
GitHub	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
OSV	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem	package	affected	fixed in
pypi	django	>=6.0, <6.0.4 >=5.2, <5.2.13 >=4.2, <4.2.30	6.0.4 5.2.13 4.2.30
bitnami	django	>=4.2.0, <4.2.30 >=5.2.0, <5.2.13 >=6.0.0, <6.0.4	4.2.30 5.2.13 6.0.4

Affected products

djangoproject Django

Classification

Weakness

CWE-407 Inefficient Algorithmic Complexity

Technology feeds

Django rss critical rss

References

docs.djangoproject.com /en/dev/releases/security/
vendor-advisory, patch, advisory
djangoproject.com /weblog/2026/apr/07/security-releases/
vendor-advisory, patch, advisory
groups.google.com /g/django-announce
mailing-list, web, release-notes, article, advisory
nvd.nist.gov /vuln/detail/CVE-2026-33033
advisory, web
docs.djangoproject.com /en/dev/releases/security
web
github.com /django/django
package
github.com /pypa/advisory-database/tree/main/vulns/django/PYSEC-2026-48.yaml
web
djangoproject.com /weblog/2026/apr/07/security-releases
web
github.com /advisories/GHSA-5mf9-h53q-7mhq
advisory

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary