---
id: CVE-2026-87802
title: >-
  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
  permission…
summary: >-
  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
  permission…
severity: critical
cvss: 9.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'
cwe:
  - CWE-347
vendor: Apache Software Foundation
product: 'org.apache.syncope:syncope-sra'
affected:
  - 'org.apache.syncope:syncope-sra >= 3.0.0-M0 <= 3.0.16'
  - 'org.apache.syncope:syncope-sra >= 4.0.0-M0 <= 4.0.7'
  - 'org.apache.syncope:syncope-sra >= 4.1.0-M0 <= 4.1.2'
published: '2026-09-14'
updated: '2026-09-14'
sourceUpdated: '2026-09-14T20:58:48.430'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-87802'
references:
  - url: 'https://lists.apache.org/thread/gx83cootj00kn8hqd73x1bp8441np33d'
    label: security@apache.org
  - url: 'http://www.openwall.com/lists/oss-security/2026/09/14/25'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-09-14T19:39:06.982847Z'
ingestedAt: '2026-09-14T15:23:07.463Z'
epss: 0.00257
epssPercentile: 0.17666
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.