Improper Validation in Pretix SSO Setup Affects Authentication Mechanism
CVE-2026-101274

6.9MEDIUM

Key Information:

Vendor

Pretix

Status
Vendor
CVE Published:
28 October 2026

What is CVE-2026-101274?

In an SSO configuration using Pretix as the identity provider, the system fails to adequately validate the ‘response_type’ in authorization requests. This vulnerability occurs when the SSO client is limited to a specific response type, such as ‘code’, but can still accept unauthorized types like ‘id_token’. If an attacker exploits this flaw by using JavaScript on a specified redirect_uri, they may receive a valid access token, bypassing intended security measures and allowing potential unauthorized access to user accounts.

References

https://pretix.eu/about/en/blog/20261028-release-2026-8-1/
vendor-advisory

CVSS V4

Score:
6.9
Severity:
MEDIUM
Confidentiality:
High
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Ravi Gohel
.