Junglewise Threat Intelligence

CVE-2026-87785: Apache Syncope authentication bypass by JWT spoofing

CVE-2026-87785 · Severity: critical · CVSS 9.1 · Published 2026-09-14

Vendors: Apache.

Executive brief

Apache Syncope is an identity and access management platform used to manage user accounts, roles, and permissions. When JWT key configuration settings are exposed, an attacker who successfully authenticates can forge tokens to impersonate other users and escalate their privileges, potentially gaining administrative access and compromising the entire identity system.

Technical details

This vulnerability is an authentication bypass resulting from insufficient JWT token validation. When JWKS (JSON Web Key Set) configuration details are disclosed, an authenticated attacker can craft forged JWT tokens by spoofing another user's identity and privileges. The vulnerability affects the internal JWT authentication mechanism across multiple major versions (3.0.x, 4.0.x, 4.1.x) of Apache Syncope. Exploitation requires prior successful authentication to obtain a valid JWT, but the attacker can then escalate to any privilege level by manipulating the token claims. Patches are available in versions 4.0.8 and 4.1.3; version 3.0.x users require an upgrade path evaluation.

Affected products

  • Apache Syncope 3.0.0-M0 through 3.0.16, 4.0.0-M0 through 4.0.7, 4.1.0-M0 through 4.1.2

Timeline

  • 2026-09-14: disclosed
  • 2026-09: patched: Fixes available in versions 4.0.8 and 4.1.3

References