Compliance-trestle (Trestle) is a Python SDK and command-line tool for managing OSCAL compliance documents. In versions before 3.12.4 and versions 4.0.0 through 4.0.3, Trestle is vulnerable to server-side template injection that can lead to remote code execution. This occurs because the MDCleanInclude and MDSectionInclude Jinja2 tags re-parse untrusted Markdown content as template source code using a non-sandboxed jinja2.Environment. An attacker who controls content that Trestle renders, such as a crafted workspace Markdown file, a third-party SSP document, or a YAML lookup-table value, can inject a Jinja2 expression that traverses Python object internals to execute arbitrary operating system commands in the context of the Trestle process. This issue is fixed in versions 3.12.4 and 4.1.0.
https://github.com/oscal-compass/compliance-trestle/security/advisories/GHSA-jw39-3688-r4rx
https://github.com/oscal-compass/compliance-trestle/commit/5335ff873a2a68eb7de43df029bea09cadff22fd
https://github.com/oscal-compass/compliance-trestle/commit/0f82d19bd42f9cc0f1b3acd7fc3f6dafe3b6ae10