CVSS v3
9.8
CRITICAL
EPSS Score
1.1 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
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 Gr
Technical details
- Published
- 2026-07-20
- Last Modified
- 2026-07-21
Frequently asked questions
What is 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 Gr
Is CVE-2026-53421 actively exploited?
Active exploitation of CVE-2026-53421 has not been confirmed. Its EPSS score was 1.1% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2026-53421?
CVE-2026-53421 has a CVSS v3 base score of 9.8 (CRITICAL severity).
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