The vulnerability arises in the FileSystemLoader and CachingFileSystemLoader of Python Liquid when an absolute path is supplied to resolve a file. Because the loaders do not enforce the defined search path, a malicious template author can include and render files located outside the intended directory. If those files contain valid Liquid markup and the application process can read them, the data will be displayed in the rendered output, allowing an attacker to read arbitrary host files and compromise confidentiality.

All releases of the Python Liquid engine prior to version 2.2.0 are affected. The maintainer, jg‑rp, fixed the issue in 2.2.0. No specific sub‑version data was provided, so any installation older than 2.2.0 needs updating.

The CVSS score of 8.2 classifies this flaw as high severity. It is not listed in CISA's KEV catalog, indicating no known active exploitation. The EPSS score is not available. The likely attack vector is a template author who can supply an absolute file path to {% include %} or {% render %}. Based on the description, it is inferred that the attacker must be able to influence template rendering within the application, such as via a web interface that accepts user‑generated templates. If such control exists, the attacker can reference any readable file on the host system and retrieve its contents.