CVE-2025-64458

Published Nov 5, 2025

Last updated 2 months ago

Python

Django

Overview

AI description

Automated description summarized from trusted sources.

CVE-2025-64458 affects Django's HTTP redirect handling on Windows systems. The vulnerability lies in the `HttpResponseRedirect` and `HttpResponsePermanentRedirect` functions. It is caused by slow NFKC normalization in Python on Windows. An attacker could exploit this by sending crafted URLs with excessive Unicode characters. This can cause Django's redirect functions to consume large amounts of CPU time, potentially leading to performance degradation or a denial-of-service. Django versions 5.2, 5.1, 4.2, and the beta version 6.0 are affected. Patches have been released in versions 5.2.8, 5.1.14, and 4.2.26.

Description: An issue was discovered in 5.1 before 5.1.14, 4.2 before 4.2.26, and 5.2 before 5.2.8. NFKC normalization in Python is slow on Windows. As a consequence, `django.http.HttpResponseRedirect`, `django.http.HttpResponsePermanentRedirect`, and the shortcut `django.shortcuts.redirect` were subject to a potential denial-of-service attack via certain inputs with a very large number of Unicode characters. 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.
Source: 6a34fbeb-21d4-45e7-8e0a-62b95bc12c92
NVD status: Analyzed
Products: django

Risk scores

CVSS 3.1

Type: Secondary
Base score: 7.5
Impact score: 3.6
Exploitability score: 3.9
Vector string: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity: HIGH

Weaknesses

6a34fbeb-21d4-45e7-8e0a-62b95bc12c92: CWE-407

Hype score: Not currently trending

Configurations

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  {
    "nodes": [
      {
        "negate": false,
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:djangoproject:django:*:*:*:*:*:*:*:*",
            "vulnerable": true,
            "matchCriteriaId": "5FC7EBE0-A60A-4083-9FB7-E4ADCD2B5F37",
            "versionEndExcluding": "4.2.26",
            "versionStartIncluding": "4.2"
          },
          {
            "criteria": "cpe:2.3:a:djangoproject:django:*:*:*:*:*:*:*:*",
            "vulnerable": true,
            "matchCriteriaId": "9F3A5471-02DB-428E-815E-516057A901FF",
            "versionEndExcluding": "5.1.14",
            "versionStartIncluding": "5.1"
          },
          {
            "criteria": "cpe:2.3:a:djangoproject:django:*:*:*:*:*:*:*:*",
            "vulnerable": true,
            "matchCriteriaId": "F56E9016-F93A-4DAE-8070-D3A4909F00A4",
            "versionEndExcluding": "5.2.8",
            "versionStartIncluding": "5.2"
          }
        ],
        "operator": "OR"
      }
    ]
  }
]

References

Sources include official advisories and independent security research.