What is CVE-2026-15337?
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.
The record classifies CVE-2026-15337 under weakness class CWE-789. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 67 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 5.3 — MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - CVSS v4.0 base score
- 6.9
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 - EPSS (FIRST)
- 0.5% probability of exploitation in the next 30 days, higher than 46.5% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 4.5/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-08-04
Is CVE-2026-15337 being exploited?
It currently carries a trending score of 30 in the Threadlinqs vulnerability feed.
Affected products and versions
- djangoproject: Django
How to fix CVE-2026-15337
No vendor patch reference has been recorded for CVE-2026-15337 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2026-15337
1 tracked threat in the Threadlinqs corpus references CVE-2026-15337, either in the campaign’s CVE list or as an indicator on the campaign record.
Sources
Enriched from CVE.org, FIRST EPSS. Last verified by Threadlinqs on .
Vendor advisory and patch
- docs.djangoproject.com — vendor advisory
- github.com — patch
- github.com — patch (5b3523d29be25948e1dd90b3863a002f00fc865f)
- github.com — patch (224dbc832586ad5cfb0237c2ff30d14baeaddc6f)
- github.com — patch (c72a5dbb64d0777f3f471f1be94e8b2ca91e0959)
Mailing list and disclosure
Showing 6 of 7 recorded references.