{"id":"CVE-2025-27556","aliases":["BIT-django-2025-27556","GHSA-wqfg-m96j-85vm","PYSEC-2025-14"],"url":"https://o3.security/vulnerability/CVE-2025-27556","summary":"Django Potential Denial of Service (DoS) on Windows ","details":"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.","published":"2025-04-02T00:00:00Z","modified":"2026-08-12T03:51:11.404925443Z","cvss":{"score":5.8,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"django","fixedVersion":"5.0.14"},{"ecosystem":"PyPI","name":"django","fixedVersion":"5.1.8"}],"fix":{"url":"https://github.com/django/django/commit/2cb311f7b069723027fb5def4044d1816d7d2afd","label":"django/django@2cb311f"},"references":[{"type":"WEB","url":"http://www.openwall.com/lists/oss-security/2025/04/02/2"},{"type":"WEB","url":"https://docs.djangoproject.com/en/dev/releases/security/"},{"type":"WEB","url":"https://groups.google.com/g/django-announce"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/27xxx/CVE-2025-27556.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-27556"},{"type":"ARTICLE","url":"https://www.djangoproject.com/weblog/2025/apr/02/security-releases/"},{"type":"WEB","url":"https://github.com/django/django/commit/2cb311f7b069723027fb5def4044d1816d7d2afd"},{"type":"WEB","url":"https://github.com/django/django/commit/39e2297210d9d2938c75fc911d45f0e863dc4821"},{"type":"WEB","url":"https://github.com/django/django/commit/8c6871b097b6c49d2a782c0d80d908bcbe2116f1"},{"type":"WEB","url":"https://github.com/django/django/commit/edc2716d01a6fdd84b173c02031695231bcee1f8"},{"type":"WEB","url":"https://docs.djangoproject.com/en/dev/releases/security"},{"type":"PACKAGE","url":"https://github.com/django/django"},{"type":"WEB","url":"https://github.com/pypa/advisory-database/tree/main/vulns/django/PYSEC-2025-14.yaml"},{"type":"WEB","url":"https://www.djangoproject.com/weblog/2025/apr/02/security-releases"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:11.404925443Z"}}