CVE-2026-53421

criticalCVSS 9.8covered by 1 sourcefirst seen 2026-07-20

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.

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Exploitation outlook

Low exploitation risk0.68% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 49% of all EPSS-scored CVEs.

Advisory coverage (1)

criticalCVE-2026-53421: Improper Isolation or Compartmentalization vulnerability in Apache Syncope. An administrator w…nvd · 2026-07-20

External references

NVD record for CVE-2026-53421

CVE.org record

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