CVE-2026-84429
Potential denial-of-service vulnerability in HTTP header parsing
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Description
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.
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
- https://docs.djangoproject.com/en/dev/releases/security/
- https://github.com/django/django/commit/7ff7fcc0508864a4bc39693128ace38b1e95a890
- https://github.com/django/django/commit/de56deeabd4c48dfb5193f0001469d80102fb367
- https://github.com/django/django/commit/3d8f121695c21234aff3071de0d38b6bd38c3f52
- https://github.com/django/django/commit/6ecd66e09a383be004a78a3a738ea9727ff07b0e
References (7)
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