CVE-2026-54757

Deferred Deferred - Pending Action

Server-Side Template Injection in Trestle

Publication date: 2026-08-25

Last updated on: 2026-09-09

Assigner: GitHub, Inc.

Description

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.

CVSS Scores

EPSS Scores

Probability:
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Meta Information

Published

2026-08-25

Last Modified

2026-09-09

Generated

2026-09-15

AI Q&A

2026-08-26

EPSS Evaluated

2026-09-14

NVD

CVE-2026-54757

Affected Vendors & Products

Vendor	Product	Version / Range
trestle	compliance-trestle	From 4.0.0 (inc) to 4.0.3 (inc)
trestle	compliance-trestle	3.12.4
trestle	compliance-trestle	4.1.0

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-94	The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.

Attack-Flow Graph

Executive Summary

Compliance-trestle (Trestle) is a Python SDK for managing OSCAL compliance documents. Versions before 3.12.4 and 4.0.0 through 4.0.3 are vulnerable to server-side template injection. This allows remote code execution because MDCleanInclude and MDSectionInclude Jinja2 tags re-parse untrusted Markdown as template source code without sandboxing. Attackers can inject Jinja2 expressions to execute arbitrary OS commands.

Detection Guidance

Check installed versions of compliance-trestle with pip show trestle or pip list. If using versions before 3.12.4 or 4.0.0 through 4.0.3, the system is vulnerable. Inspect Markdown files or SSP documents for Jinja2 expressions that may indicate template injection attempts.

Impact Analysis

If you use affected Trestle versions, an attacker who controls rendered content (e.g., Markdown files, SSP documents, or YAML values) could execute malicious commands on your system. This could lead to data theft, system compromise, or unauthorized access, depending on the attacker's goals.

Compliance Impact

This vulnerability could compromise compliance by enabling unauthorized access or data breaches. GDPR requires protecting personal data, and HIPAA mandates safeguarding health information. Exploitation could lead to violations, legal penalties, or reputational damage due to failed compliance checks.

Mitigation Strategies

Upgrade compliance-trestle to version 3.12.4 or 4.1.0 or later immediately. Avoid rendering untrusted Markdown or SSP documents until patched. Review workspace files for suspicious Jinja2 expressions or command-like patterns.

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