CVE-2026-53405 Apache Software Foundation CVE debrief

Who should care

Users of Apache Syncope versions 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 should be aware of this vulnerability and take steps to mitigate it by upgrading to a fixed version. This includes administrators, security teams, and operators responsible for maintaining and securing Apache Syncope deployments.

Technical summary

The vulnerability allows an administrator with adequate entitlements to import arbitrary BPMN process definitions via the REST API and then start the process. When a BPMN process containing a Groovy scriptTask is imported and started, the Groovy script is executed directly on the server, with no sandbox. This issue has a CVSS score of 9.8 and is considered CRITICAL. Affected versions include 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.

Defensive priority

High

Recommended defensive actions

• Upgrade to version 4.0.7 or 4.1.2
• Restrict access to the REST API
• Monitor for suspicious activity
• Implement additional security measures to prevent exploitation
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record was published on 2026-07-20T15:16:42.987Z and was last modified on 2026-07-21T16:17:14.853Z. The NVD entry is currently Undergoing Analysis. 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 wrapping Flowable's Groovy scriptTasks with security sandbox. Evidence is limited, and defenders should verify affected scope and vendor guidance.

Official resources