Potential exposure of private data via missing Vary: Authorization in UpdateCacheMiddleware
CVE-2026-35193

2.3LOW

Key Information:

Vendor

Djangoproject

Status
Django
Vendor
CVE Published:
3 June 2026

What is CVE-2026-35193?

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.

Affected Version(s)

Django 6.0 < 6.0.6

Django 5.2 < 5.2.15

Django 6.0.6

References

https://docs.djangoproject.com/en/dev/releases/security/
vendor-advisory
https://groups.google.com/g/django-announce
mailing-list
https://www.djangoproject.com/weblog/2026/jun/03/security...
vendor-advisory

CVSS V4

Score:
2.3
Severity:
LOW
Confidentiality:
Low
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Shai Berger
Jacob Walls
Natalia Bidart
.