CVE-2026-78330: Apache Syncope: Privilege escalation for admin user via JWT authentication

[Francesco Chicchiriccò <ilgrosso () apache org>]

Severity: moderate 

Affected versions:

- Apache Syncope (org.apache.syncope.core:syncope-core-spring) 3.0.0-M0 through 3.0.16
- Apache Syncope (org.apache.syncope.core:syncope-core-spring) 4.0.0-M0 through 4.0.7
- Apache Syncope (org.apache.syncope.core:syncope-core-spring) 4.1.0-M0 through 4.1.2

Description:

Incorrect privilege assignment vulnerability in Apache Syncope.

When the configured JWKS settings for internal JWT authentication are disclosed (at least protocol and key), an 
attacker can obtain admin privileges after completing a successful authentication and obtaining a valid low-privileges 
JWT.



This issue affects Apache Syncope: from 3.0.0-M0 through 3.0.16, from 4.0.0-M0 through 4.0.7, from 4.1.0-M0 through 
4.1.2.



Users are recommended to upgrade to version 4.0.8 / 4.1.3, which fix this issue.

Credit:

Moritz Theile (finder)

References:

https://syncope.apache.org/
https://www.cve.org/CVERecord?id=CVE-2026-78330