CVE-2026-1285: Potential denial-of-service vulnerability in django.utils.text.Truncator HTML methods

Vulnerability summary

CVE-2026-1285 is a high (CVSS 7.5) Inefficient Algorithmic Complexity vulnerability in djangoproject django. EPSS estimates a 1.11% chance of exploitation in the next 30 days, higher than 66% of scored vulnerabilities.

Timeline

1. 03-02-2026
   PublishedVulnerability first disclosed.
2. 03-02-2026
   Last modifiedVulnerability information updated.

Description

An issue was discovered in 6.0 before 6.0.2, 5.2 before 5.2.11, and 4.2 before 4.2.28. `django.utils.text.Truncator.chars()` and `Truncator.words()` methods (with `html=True`) and the `truncatechars_html` and `truncatewords_html` template filters allow a remote attacker to cause a potential denial-of-service via crafted inputs containing a large number of unmatched HTML end tags. 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.

• CWE-407Inefficient Algorithmic ComplexityAn algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.