# CVE-2026-35193: Django UpdateCacheMiddleware information disclosure via missing Vary header

Source: https://junglewise.ai/threats/cve-2026-35193-django-updatecachemiddleware-information-disclosure-via-missing  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-03. Updated: 2026-08-07  
License: CC BY 4.0 with a link back

CVE-2026-35193 · Severity: medium · CVSS 4 · Published 2026-06-03

A vulnerability in the Django web framework's caching system could allow unauthorized users to view private data. When a website uses certain caching settings, the system may fail to distinguish between public content and content intended only for specific logged-in users. This could result in sensitive information being served to the wrong person if they visit the same web address.

Technologies: [Django (PyPI)](https://junglewise.ai/threats/technologies/django). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2026-35193 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-35193 being exploited in the wild.

**How severe is CVE-2026-35193?** Medium severity, with a CVSS score of 4, published 3 June 2026.

**Which products and versions are affected?** Django (PyPI) ECOSYSTEM:introduced=5.2,fixed=5.2.15,introduced=6.0,fixed=6.0.6, ECOSYSTEM:introduced=5.2.0,fixed=5.2.15.

**Is there a fix for CVE-2026-35193?** 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-2026-35193 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-35193?** 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

  ```sh
  pip install "Django>=6.0.6"
  ```


## Technical details

A vulnerability exists in django.middleware.cache.UpdateCacheMiddleware where the 'Authorization' header is not automatically added to the 'Vary' response header. This occurs when a request includes an Authorization header but the response does not specify 'Cache-Control: public'. Consequently, a downstream cache or the Django internal cache might serve a response intended for an authenticated user to an unauthenticated attacker requesting the same URL. This is classified as a 'Use of Cache Containing Sensitive Information' (CWE-524). The issue is resolved in Django versions 5.2.15 and 6.0.6.

## Affected products

- Django Software Foundation Django >= 5.2.0, < 5.2.15
- Django Software Foundation Django >= 6.0.0, < 6.0.6

## Identifiers

- CVE-2026-35193
- GHSA-qpc8-7fxc-cm4p
- PYSEC-2026-197

## Timeline

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

## References

- [https://api.github.com/users/cgurnik](https://api.github.com/users/cgurnik)
- [https://github.com/cgurnik](https://github.com/cgurnik)
- [https://api.github.com/users/cgurnik/gists%7B/gist_id%7D](https://api.github.com/users/cgurnik/gists%7B/gist_id%7D)
- [https://api.github.com/users/cgurnik/repos](https://api.github.com/users/cgurnik/repos)
- [https://avatars.githubusercontent.com/u/720008?v=4](https://avatars.githubusercontent.com/u/720008?v=4)
- [https://api.github.com/users/cgurnik/events%7B/privacy%7D](https://api.github.com/users/cgurnik/events%7B/privacy%7D)

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