GlassFish's gadget handler is vulnerable to RCE
Date: 2026-05
Affected: maven/org.glassfish.jsftemplating:jsftemplating, maven/org.glassfish.main.admingui:admingui
Attack vector: rce
Category: vulnerability-disclosure
Severity: Critical
CVE: CVE-2026-2587
CWE: CWE-917
CVSS: 9.6 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H)

A critical Remote Code Execution (RCE) vulnerability was identified in the server-side template rendering mechanism used by the Glassfish gadget handler. The application processes .xml files and evaluates user-supplied values within a context where Expression Language (EL) “expressions” are processed without proper sanitization or escaping. By injecting expressions such as #{7*7}, the server returns 49, confirming server-side EL evaluation. This issue allows a remote attacker to fully compromise the underlying host, enabling capabilities as reading/modifying data, executing arbitrary commands, persistence, and lateral movement.


Mitigations:

Architectural layers (MAESTRO):