CVE-2026-87785

Authentication bypass by spoofing vulnerability in Apache Syncope. When the configured JWKS settings for internal JWT authentication are disclosed (at least protocol and key), an attacker can spoof another user's privileges after completing a successful authentication and obtaining a valid 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.

Score

CVSS 3.1 9.1 Critical

Status

Deferred - security@apache.org

Published

2026-09-14

Last modified

2026-09-14

Weaknesses

CWE-290

Affected products

• Apache Syncope (Apache Software Foundation)

References

• https://lists.apache.org/thread/3t3om8mny7ng52q053pdzpmtdtosnqoo
• http://www.openwall.com/lists/oss-security/2026/09/14/24