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.

Database specific

{
    "unresolved_ranges": [
        {
            "extracted_events": [
                {
                    "introduced": "5.0"
                },
                {
                    "fixed": "5.0.14"
                },
                {
                    "introduced": "5.1"
                },
                {
                    "fixed": "5.1.8"
                }
            ],
            "source": "AFFECTED_FIELD"
        },
        {
            "extracted_events": [
                {
                    "introduced": "5.0"
                },
                {
                    "fixed": "5.0.14"
                },
                {
                    "introduced": "5.1"
                },
                {
                    "fixed": "5.1.8"
                }
            ],
            "source": "CPE_FIELD"
        },
        {
            "extracted_events": [
                {
                    "introduced": "5.1"
                },
                {
                    "fixed": "5.1.8"
                },
                {
                    "introduced": "5.0"
                },
                {
                    "fixed": "5.0.14"
                }
            ],
            "source": "DESCRIPTION"
        }
    ],
    "cna_assigner": "mitre",
    "cwe_ids": [
        "CWE-770"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/27xxx/CVE-2025-27556.json"
}

References

Affected packages

Git / github.com/django/django

Affected ranges

Type

GIT

Repo

https://github.com/django/django

Events

Introduced

52821001bb62b764d73e63812133f199b8fef9eb

Fixed

7c128112a6adff20b6d67a02c4098a2c10f88191

Introduced

84d09a547fe35e10018ab242602ca76c29ca91a1

Fixed

5773bc9cf929f4648da30cb9c472b816bb4db771

Database specific

Show details

{
    "extracted_events": [
        {
            "introduced": "5.0"
        },
        {
            "fixed": "5.0.14"
        },
        {
            "introduced": "5.1"
        },
        {
            "fixed": "5.1.8"
        }
    ],
    "source": "CPE_RANGE",
    "cpe": "cpe:2.3:a:djangoproject:django:*:*:*:*:*:*:*:*"
}

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-27556.json"