CVE-2026-87802

CriticalCVSS 9.1/10Last modified Sep 14, 2026

Description

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.

Metrics

CVSS 3.1 9.1/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Weakness enumeration

Affected software

No affected versions have been published.

Timeline

Published
Sep 14, 2026
Last modified
Sep 14, 2026
NVD status
Deferred

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CVE-2026-87802: Critical severity, CVSS 9.1 | Vulnix