CVE-2024-22533

Vulnerability

Overview Beetl versions prior to 3.15.12 are vulnerable to server-side template injection (SSTI). The DefaultNativeSecurityManager applies a blacklist to filter malicious template expressions, but the filtering is insufficient and can be bypassed [1][3].

Exploitation

An attacker who can control the template content—for instance, through user-supplied input that is rendered without proper sanitization—can craft a payload that evades the blacklist. This allows the injection of arbitrary Java code or expressions, leading to remote code execution [3].

Impact

Successful exploitation grants the attacker the ability to execute arbitrary code on the server, potentially compromising the entire application and underlying infrastructure.

Mitigation

The issue is fixed in Beetl version 3.15.12. Users should upgrade to this version or later [2]. There is no workaround available if the template source is untrusted.