Vulnerability · Published Sep 14, 2026 · Assigned by apache

CVE-2026-87785Apache Syncope: JWT subject spoofing

Critical 9.1

In plain English

A critical-severity authentication bypass by spoofing in Apache Syncope from Apache Software Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 46% of all known vulnerabilities).

Severity (CVSS 3.1)9.1Critical
Exploit odds (30 days)0.5%top 53.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

VendorProductVersions
Apache Software Foundation Apache Syncope 3.0.0-M0 – through 3.0.164.0.0-M0 – through 4.0.74.1.0-M0 – through 4.1.2

Weakness: CWE-290 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

References