CVE-2026-53421 in Syncope
Summary
by MITRE • 07/20/2026
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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Analysis
by VulDB Data Team • 07/20/2026
The vulnerability described represents a critical improper isolation or compartmentalization weakness within Apache Syncope's connector subsystem that fundamentally compromises the system's security boundaries. This flaw exists in versions ranging from 3.0.0-M0 through 3.0.16, 4.0.0-M0 through 4.0.6, and 4.1.0-M0 through 4.1.1, creating a significant attack surface that allows authenticated administrators to escalate privileges and achieve remote code execution. The vulnerability specifically leverages the scripted connector capabilities of REST and SQL connectors which are designed to execute Groovy scripts for data synchronization and integration purposes.
The technical exploitation occurs through a direct compromise of the Groovy script execution environment within the connector subsystem, where administrative users with appropriate entitlements can inject malicious Groovy code that bypasses normal security restrictions. This represents a classic sandbox escape vulnerability where the intended security boundaries around script execution are insufficiently enforced, allowing privilege escalation from administrative access to full system compromise. The flaw operates at the intersection of inadequate input validation and overly permissive script execution environments, creating a pathway for arbitrary code execution that fundamentally undermines the principle of least privilege.
From an operational impact perspective, this vulnerability transforms what should be a controlled administrative function into a potential gateway for complete system compromise. Attackers can leverage legitimate administrative capabilities to execute arbitrary commands on the underlying system, potentially leading to data exfiltration, system infiltration, or further lateral movement within the network infrastructure. The attack vector is particularly concerning because it requires only administrative privileges rather than elevated system access, making it accessible to insiders or compromised administrator accounts. This vulnerability directly impacts the integrity and confidentiality of identity management systems that rely on Apache Syncope for user provisioning and authentication services.
The remediation strategy implemented in versions 4.0.7 and 4.1.2 addresses this through enhanced Groovy security sandboxing mechanisms that properly isolate script execution from system-level operations. This fix aligns with established security practices for preventing sandbox escape vulnerabilities and demonstrates adherence to the principle of defense in depth. The hardening measures likely include stricter class loader restrictions, limited access to system resources, and enhanced input validation for script content. Organizations should prioritize immediate upgrade to these patched versions while implementing additional monitoring for suspicious administrative activities that might indicate exploitation attempts. This vulnerability type is categorized under CWE-276 as improper privilege management and relates to ATT&CK technique T1059 for command and scripting interpreter, highlighting the need for comprehensive security controls around privileged access and script execution environments.
The broader implications of this vulnerability extend beyond immediate exploitation potential to highlight systemic issues in identity and access management platforms. Organizations relying on Apache Syncope for user provisioning and synchronization must evaluate their overall security posture, particularly regarding how administrative privileges are managed and how external integration points are secured. This vulnerability underscores the critical importance of maintaining up-to-date software versions and implementing robust monitoring for anomalous administrative activities that could indicate unauthorized privilege escalation attempts.