Django 5.2/6.0 Auth Header missing from Vary causing cache leak
CVE-2026-35193 Published on June 3, 2026

Potential exposure of private data via missing Vary: Authorization in UpdateCacheMiddleware
An issue was discovered in Django 5.2 before 5.2.15 and 6.0 before 6.0.6. `django.middleware.cache.UpdateCacheMiddleware` in Django does not add `Authorization` to the `Vary` response header for requests bearing that header without `Cache-Control: public`, which allows remote attackers to read private cached responses via unauthenticated requests to the same URL. 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 Shai Berger for reporting this issue.

Vendor Advisory Vendor Advisory NVD

Timeline

Initial report received.

Vulnerability confirmed. 35 days later.

Security release issued. 36 days later.

Weakness Type

Use of Cache Containing Sensitive Information

The code uses a cache that contains sensitive information, but the cache can be read by an actor outside of the intended control sphere. Applications may use caches to improve efficiency when communicating with remote entities or performing intensive calculations. A cache maintains a pool of objects, threads, connections, pages, financial data, passwords, or other resources to minimize the time it takes to initialize and access these resources. If the cache is accessible to unauthorized actors, attackers can read the cache and obtain this sensitive information.


Products Associated with CVE-2026-35193

Want to know whenever a new CVE is published for Django Project Django? stack.watch will email you.

Django Project Django
 

Affected Versions

djangoproject Django:

Exploit Probability

EPSS
0.04%
Percentile
11.49%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.