Vulnerability in Apache Syncope
CVE-2026-53421
Improper Isolation or Compartmentalization vulnerability in Apache Syncope. An administrator with adequate entitlements can achieve remote code execution through the connector subsystem by relying on scripted connectors' (REST and SQL) capability to run Groovy scripts. This issue affects Apache Syncope: from 3.0.0-M0 through 3.0.16, from 4.0.0-M0 Through 4.0.6, from 4.1.0-M0 through 4.1.1. Users are recommended to upgrade to version 4.0.7 / 4.1.2, which fix this issue by hardening the Groovy security sandbox.
EPSS: 0.007 (49.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Apache Syncope
- Apache Software Foundation Syncope — versions 3.0.0-M0, 4.0.0-M0, 4.1.0-M0
Weakness classification (CWE)
References
- security@apache.org (vendor-advisory, Mailing List, Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-53421?
- CVE-2026-53421 is a critical-severity vulnerability in Apache Syncope, classified under CWE-653. CVSS score: 9.8/10. Published 2026-07-20.
- How severe is CVE-2026-53421?
- Critical severity. CVSS v3 base score is 9.8 out of 10.