Vulnerability in Apache Software Foundation Syncope
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.
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.
Affected products
Weakness classification (CWE)
References
- security@apache.org (vendor-advisory)
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2026-87785?
- CVE-2026-87785 is a critical-severity vulnerability in Apache Software Foundation Syncope, classified under Authentication Bypass by Spoofing. CVSS score: 9.1/10. Published 2026-09-14.
- How severe is CVE-2026-87785?
- Critical severity. CVSS v3 base score is 9.1 out of 10.