Is CVE-2026-8404 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-8404 being exploited in the wild.

How severe is CVE-2026-8404?

Low severity, with a CVSS score of 3.1, published 3 June 2026.

Which products and versions are affected?

Django (PyPI) ECOSYSTEM:introduced=0,fixed=5.2.15, ECOSYSTEM:introduced=5.2,fixed=5.2.15,introduced=6.0,fixed=6.0.6.

Is there a fix for CVE-2026-8404?

Yes. Django (PyPI): upgrade to 5.2.15, 6.0.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-8404 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-8404?

Check whether you run Django (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-8404: Django UpdateCacheMiddleware information disclosure via case-sensitive headers

CVE-2026-8404 · Severity: low · CVSS 3.1 · Published 2026-06-03

A vulnerability in Django's caching system could allow unauthorized users to view sensitive information that was intended to be private. This occurs because the system fails to correctly recognize certain security instructions if they are written in capital letters, leading it to store and serve data that should not be cached. Organizations using affected versions of Django for web applications may inadvertently expose user-specific or private data to other visitors.

Technologies: Django (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-8404 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-8404 being exploited in the wild.
How severe is CVE-2026-8404?: Low severity, with a CVSS score of 3.1, published 3 June 2026.
Which products and versions are affected?: Django (PyPI) ECOSYSTEM:introduced=0,fixed=5.2.15, ECOSYSTEM:introduced=5.2,fixed=5.2.15,introduced=6.0,fixed=6.0.6.
Is there a fix for CVE-2026-8404?: Yes. Django (PyPI): upgrade to 5.2.15, 6.0.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-8404 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-8404?: Check whether you run Django (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Django (PyPI): upgrade to 5.2.15, 6.0.6 or later
```
pip install "Django>=6.0.6"
```

Technical details

A case-sensitivity issue (CWE-178) exists in django.middleware.cache.UpdateCacheMiddleware. The middleware does not match Cache-Control response directives case-insensitively, meaning directives like 'no-store' in mixed or uppercase (e.g., 'No-Store') are ignored. This results in responses being cached when they should have been excluded, allowing remote attackers to potentially access sensitive data from the cache. The vulnerability is fixed in Django versions 5.2.15 and 6.0.6.

Affected products

Django Software Foundation Django < 5.2.15, >= 6.0.0, < 6.0.6

Identifiers

CVE-2026-8404
GHSA-8cjm-8mp7-r2xf
PYSEC-2026-201

Timeline

2026-06-03: disclosed
2026-06-03: advisory
2026-06-03: patched

References

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