CVE-2026-84429
Potential denial-of-service vulnerability in HTTP header parsing
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.
INFO
Published Date :
Oct. 6, 2026, 2:17 p.m.
Last Modified :
Oct. 6, 2026, 2:17 p.m.
Remotely Exploit :
Yes !
Source :
6a34fbeb-21d4-45e7-8e0a-62b95bc12c92
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | MITRE-CVE | ||||
| CVSS 3.1 | MEDIUM | 6a34fbeb-21d4-45e7-8e0a-62b95bc12c92 | ||||
| CVSS 4.0 | MEDIUM | 6a34fbeb-21d4-45e7-8e0a-62b95bc12c92 |
Solution
- Update Django to version 6.1.2 or later.
- Update Django to version 6.0.9 or later.
- Update Django to version 5.2.18 or later.
- Apply relevant patches for older Django versions.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-84429.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-84429 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-84429
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-84429 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-84429 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by 6a34fbeb-21d4-45e7-8e0a-62b95bc12c92
Oct. 06, 2026
Action Type Old Value New Value Added 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Added CWE CWE-407 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/84xxx/CVE-2026-84429.json">CVE-2026-84429</a> Added Reference https://docs.djangoproject.com/en/dev/releases/security/ Added Reference https://github.com/django/django/commit/3d8f121695c21234aff3071de0d38b6bd38c3f52 Added Reference https://github.com/django/django/commit/6ecd66e09a383be004a78a3a738ea9727ff07b0e Added Reference https://github.com/django/django/commit/7ff7fcc0508864a4bc39693128ace38b1e95a890 Added Reference https://github.com/django/django/commit/de56deeabd4c48dfb5193f0001469d80102fb367 Added Reference https://groups.google.com/g/django-announce Added Reference https://www.djangoproject.com/weblog/2026/oct/06/security-releases/