CVE-2026-25673: Djangoproject Django

High severity, CVSS 7.5. EPSS: 1.1% chance of exploitation in the next 30 days.

An issue was discovered in 6.0 before 6.0.3, 5.2 before 5.2.12, and 4.2 before 4.2.29. `URLField.to_python()` in Django calls `urllib.parse.urlsplit()`, which performs NFKC normalization on Windows that is disproportionately slow for certain Unicode characters, allowing a remote attacker to cause denial of service via large URL inputs containing these characters. Earlier, unsupported Django series (such as 5.0.x, 4.1.x, and 3.2.x) were not evaluated and may also be affected. Django would like to thank Seokchan Yoon for reporting this issue.

Affected products

• Djangoproject Django: from 4.2.0, before 4.2.29 (fixed in 4.2.29); from 5.2, before 5.2.12 (fixed in 5.2.12); from 6.0, before 6.0.3 (fixed in 6.0.3)

Published 2026-03-03. Last modified 2026-07-15.