An issue was discovered in Django 5.2 before 5.2.17 and 6.0 before 6.0.8. `django.utils.translation.check_for_language()` is subject to a potential denial-of-service attack when given many distinct, very long language codes, which are retained as keys in an in-memory cache and consume process memory. Such codes reach the function through the `django.views.i18n.set_language()` view, which is not routed by default. The consumed memory is bounded, since request data is limited by the `DATA_UPLOAD_MAX_MEMORY_SIZE` setting (default 2.5 MB) and the cache holds a fixed maximum number of entries. 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 Jaeyoung Jang for reporting this issue.
https://groups.google.com/g/django-announce
https://github.com/django/django/commit/c72a5dbb64d0777f3f471f1be94e8b2ca91e0959
https://github.com/django/django/commit/5b3523d29be25948e1dd90b3863a002f00fc865f
https://github.com/django/django/commit/27137e655e442e81095f1f8f77ff3870d9fdf169
https://github.com/django/django/commit/224dbc832586ad5cfb0237c2ff30d14baeaddc6f
Published: 2026-08-04
Updated: 2026-08-04
Base Score: 5
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P
Severity: Medium
Base Score: 5.3
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Severity: Medium
Base Score: 6.9
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00521