OpenRemote is Vulnerable to Expression Injection_CVE-2026-39842

10 / 10

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Description

OpenRemote is an open-source IoT platform. Versions 1.21.0 and below contain two interrelated expression injection vulnerabilities in the rules engine that allow arbitrary code execution on the server. The JavaScript rules engine executes user-supplied scripts via Nashorn's ScriptEngine.eval() without sandboxing, class filtering, or access restrictions, and the authorization check in RulesResourceImpl only restricts Groovy rules to superusers while leaving JavaScript rules unrestricted for any user with the write:rules role. Additionally, the Groovy rules engine has a GroovyDenyAllFilter security filter that is defined but never registered, as the registration code is commented out, rendering the SandboxTransformer ineffective for superuser-created Groovy rules. A non-superuser attacker with the write:rules role can create JavaScript rulesets that execute with full JVM access, enabling remote code execution as root, arbitrary file read, environment variable theft including database credentials, and complete multi-tenant isolation bypass to access data across all realms. This issue has been fixed in version 1.22.0.

AI Analysis

Expression injection vulnerability in the rules engine of OpenRemote, allowing arbitrary code execution on the server.

Basic Information

ID CVE-2026-39842

Source GitHub_M

Published Apr 14, 2026 at 23:21

Affected Product

Vendor openremote

Product openremote

Version < 1.22.0

Affected Versions openremote openremote < 1.22.0

CWE Classification

CWE-94 CWE-917

AI Assessment

AI Score 10 / 10

AI Severity CRITICAL

Vendor OpenRemote

Product OpenRemote

Version 1.21.0 and below

References

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