The masci banks product versions before 2.4.4 contain a path traversal vulnerability (CWE-22) in all four media filters (image, audio, video, document). These filters accept user-controlled template variables as file paths and open them without any path sanitization or directory restriction. An attacker can exploit this by using '../' sequences to access arbitrary files readable by the Python process. The contents of these files are returned base64-encoded in the rendered prompt output, facilitating easy exfiltration. This vulnerability is particularly critical for applications that process user-provided template variables before sending prompts to large language models (LLMs). The vulnerability is fixed in version 2.4.4.

An unauthenticated attacker can read arbitrary files on the system running masci banks by exploiting the path traversal flaw. This can lead to disclosure of sensitive information such as environment variables, SSH private keys, cloud credentials, source code, and critical system files like /etc/passwd and /etc/shadow. The confidentiality impact is high, but there is no direct impact on integrity or availability. The vulnerability enables trivial exfiltration of sensitive data via the application’s prompt output.

Upgrade to masci banks version 2.4.4 or later, where this path traversal vulnerability has been fixed. There is no indication of any temporary or alternative mitigations. Patch status is confirmed by the vendor advisory stating the fix in 2.4.4.