CVE-2025-14550: Django Denial-of-Service via Inefficient Algorithmic Complexity
Summary
CVE-2025-14550: Django has Inefficient Algorithmic Complexity. Affects django across 3 version ranges.
>= 4.2a1, < 4.2.28
>= 5.2a1, < 5.2.11
>= 6.0a1, < 6.0.2
Fixed in 4.2.28, 5.2.11 or 6.0.2, depending on the release line you run. How to fix ↓
Also tracked for
- django · Bitnami
The same CVE-2025-14550 is tracked separately for each ecosystem and vendor. Its fix information is the same; the package and affected versions differ.
Check if this vulnerability affects your application
Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.
No signup required · Results in about 60 seconds
Background
Django is a high-level Python web framework that encourages rapid development and clean, pragmatic design. It is widely used for building web applications due to its robust features, including an ORM, authentication, and an admin interface. However, certain versions of Django are vulnerable to an issue that can lead to denial-of-service attacks when handling requests with multiple duplicate headers.
Vulnerability Detail
An issue was discovered in Django versions 6.0 before 6.0.2, 5.2 before 5.2.11, and 4.2 before 4.2.28. The vulnerability arises from the ASGIRequest component, which allows a remote attacker to craft requests with multiple duplicate headers, potentially leading to a denial-of-service condition. This vulnerability may also affect earlier unsupported versions of Django, such as 5.0.x, 4.1.x, and 3.2.x, although they were not evaluated. The severity of this vulnerability is classified as low, with a CVSS score of 2.7.
How To Fix
Latest published version: 6.1.2 as of 22 Oct 2026
pip install --upgrade "django==6.1.2"Upgrading to it may include breaking changes; the versions below are the minimum fixed release for this vulnerability.
If you can't move to the latest
The minimum fixed version depends on the release line you run.
-
>= 4.2a1, < 4.2.284.2.28pip install --upgrade "django==4.2.28" -
>= 5.2a1, < 5.2.115.2.11pip install --upgrade "django==5.2.11" -
>= 6.0a1, < 6.0.26.0.2pip install --upgrade "django==6.0.2"
Tip — Not sure which release line you're on? Vulert can find the fix for the version you are using. Scan free →
Workaround
If you cannot upgrade immediately, consider implementing input validation to filter out duplicate headers in requests. This can help mitigate the risk of denial-of-service attacks until you can apply the patch.
Conclusion
Django has a vulnerability that can lead to denial-of-service attacks through crafted requests with multiple duplicate headers. It is crucial to update to the latest patched versions to mitigate this risk. If immediate updates are not feasible, consider implementing workarounds to protect your application.
See every vulnerability recorded for django →
FAQ
CVE-2025-14550 is a vulnerability in Django that allows for potential denial-of-service attacks through crafted requests with multiple duplicate headers.
Django versions 6.0 before 6.0.2, 5.2 before 5.2.11, and 4.2 before 4.2.28 are affected. Earlier unsupported versions may also be vulnerable.
You can use Vulert to monitor and alert for open-source vulnerabilities in your software. Visit Vulert Scanner to check if your application is affected by this vulnerability without any signup.
If an immediate upgrade is not possible, implement input validation to filter out duplicate headers in requests as a temporary workaround.
The vulnerability is classified as low severity, with a CVSS score of 2.7.
Related vulnerabilities
Recent vulnerabilities recorded for django.
