CVE-2025-27556

An issue was discovered in Django 5.1 before 5.1.8 and 5.0 before 5.0.14. The NFKC normalization is slow on Windows. As a consequence, django.contrib.auth.views.LoginView, django.contrib.auth.views.LogoutView, and django.views.i18n.set_language are subject to a potential denial-of-service attack via certain inputs with a very large number of Unicode characters.

CVSS v3 5.8 MEDIUM

5.8^/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 CHANGED

References

Link	Resource
https://docs.djangoproject.com/en/dev/releases/security/	Vendor Advisory
https://groups.google.com/g/django-announce	Vendor Advisory
https://www.djangoproject.com/weblog/2025/apr/02/security-releases/	Vendor Advisory
http://www.openwall.com/lists/oss-security/2025/04/02/2	Mailing List Third Party Advisory

Configurations

Configuration 1 (hide)

AND

OR	cpe:2.3:a:djangoproject:django::::::::
	cpe:2.3:a:djangoproject:django::::::::

cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*

History

No history.

Information

Published : 2025-04-02 13:15

Updated : 2025-10-03 15:34

NVD link : CVE-2025-27556

Mitre link : CVE-2025-27556

CVE.ORG link : CVE-2025-27556

JSON object : View

Products Affected

microsoft

windows

djangoproject

django

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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