The masci banks product generates LLM prompts using a template language. Versions before 2.4.2 use jinja2.Environment() without sandboxing to render templates. If an application passes user-controlled strings as the template argument to Prompt(), it is vulnerable to SSTI, which can lead to remote code execution on the host. The vulnerability is identified as CWE-1336 (Improper Neutralization of Special Elements Used in a Template Engine) and CWE-917 (Improper Neutralization of Input During Web Page Generation). The vulnerability has a CVSS 3.1 score of 7.5 (High) with network attack vector, high impact on confidentiality, integrity, and availability, and requires user interaction with high attack complexity. The vulnerability is fixed in version 2.4.2.

Successful exploitation allows an attacker to execute arbitrary code remotely on the host system running the vulnerable version of masci banks. This compromises confidentiality, integrity, and availability of the affected system. The vulnerability requires user interaction and has a high attack complexity, but no known exploits are reported in the wild at this time.

A fix is available in masci banks version 2.4.2. Users should upgrade to version 2.4.2 or later to remediate this vulnerability. The vendor advisory from Red Hat does not indicate any alternative mitigations or that no action is required. Therefore, upgrading is the recommended remediation.