CVE-2026-87802: Apache Software Foundation Apache Syncope

Critical severity, CVSS 9.1. EPSS: 0.3% chance of exploitation in the next 30 days.

Improper verification of cryptographic signature vulnerability in Apache Syncope. When SRA is configured for OAuth 2.0 without JWKS set URI assigned, an attacker can forge arbitrary JWTs to impersonate any user identity and permissions, gaining full access to services proxied by SRA. 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.

Affected products

• Apache Software Foundation Apache Syncope: from 3.0.0-M0, up to and including 3.0.16; from 4.0.0-M0, up to and including 4.0.7; from 4.1.0-M0, up to and including 4.1.2

Published 2026-09-14. Last modified 2026-09-14.