CVE-2026-15337: Potential denial-of-service vulnerability in check_for_language()

Vulnerability summary

CVE-2026-15337 is a medium (CVSS 6.9) vulnerability in djangoproject django. EPSS estimates a 0.59% chance of exploitation in the next 30 days, higher than 48.2% of scored vulnerabilities.

Timeline

1. 04-08-2026
   PublishedVulnerability first disclosed.
2. 04-08-2026
   Last modifiedVulnerability information updated.

Description

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.

• CWE-789Memory Allocation with Excessive Size ValueThe product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated.