CVE-2026-84429

An issue was discovered in Django 6.1 before 6.1.2, 6.0 before 6.0.9, and 5.2 before 5.2.18. `django.utils.http.parse_header_parameters()` was subject to a potential denial-of-service attack due to quadratic time complexity when parsing a value with many separators inside a quoted parameter. An unauthenticated request could reach this parsing through headers such as `Accept` or `Content-Type`, for instance via the content negotiation performed by `HttpRequest.accepts()`. The per-call length limit does not bound the combined size of repeated headers. Earlier, unsupported Django series (such as 5.1.x, 5.0.x, and 4.2.x) were not evaluated and may also be affected. Django would like to thank Jisung Chae for reporting this issue.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://docs.djangoproject.com/en/dev/releases/security/
https://github.com/django/django/commit/3d8f121695c21234aff3071de0d38b6bd38c3f52
https://github.com/django/django/commit/6ecd66e09a383be004a78a3a738ea9727ff07b0e
https://github.com/django/django/commit/7ff7fcc0508864a4bc39693128ace38b1e95a890
https://github.com/django/django/commit/de56deeabd4c48dfb5193f0001469d80102fb367
https://groups.google.com/g/django-announce
https://www.djangoproject.com/weblog/2026/oct/06/security-releases/

Configurations

No configuration.

History

06 Oct 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-06 14:17

Updated : 2026-10-06 15:17

NVD link : CVE-2026-84429

Mitre link : CVE-2026-84429

CVE.ORG link : CVE-2026-84429

JSON object : View

Products Affected

No product.

CWE

CWE-407

Inefficient Algorithmic Complexity

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An unauthenticated request could reach this parsing through headers such as `Accept` or `Content-Type`, for instance via the content negotiation performed by `HttpRequest.accepts()`. The per-call length limit does not bound the combined size of repeated headers.\nEarlier, unsupported Django series (such as 5.1.x, 5.0.x, and 4.2.x) were not evaluated and may also be affected.\nDjango would like to thank Jisung Chae for reporting this issue."}], "lastModified": "2026-10-06T15:17:19.860", "sourceIdentifier": "6a34fbeb-21d4-45e7-8e0a-62b95bc12c92"}