CVE-2026-45017

Workarounds

Create a custom template loader by inheriting from FileSystemLoader and overriding resolve_path(). Use an instance of the custom loader as the loader argument when instantiating your Liquid environment.

import os
from pathlib import Path

from liquid import Environment
from liquid import FileSystemLoader
from liquid.exceptions import TemplateNotFoundError


class MyFileSystemLoader(FileSystemLoader):
    def resolve_path(self, template_name: str) -> Path:
        template_path = Path(template_name)

        if self.ext and not template_path.suffix:
            template_path = template_path.with_suffix(self.ext)

        if os.path.pardir in template_path.parts or template_path.is_absolute():
            raise TemplateNotFoundError(template_name)

        for path in self.search_path:
            source_path = path.joinpath(template_path)
            if not source_path.exists():
                continue
            return source_path

        raise TemplateNotFoundError(template_name)


env = Environment(loader=MyFileSystemLoader("path/to/templates/"))

The built-in FileSystemLoader and CachingFileSystemLoader do not guard against reading files outside their search paths when given an absolute path to resolve. This allows malicious template authors to load and render arbitrary files via the {% include %} and {% render %} tags. Targeted files would need to contain valid Liquid markup and be readable by the application process.

Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files. Typical impact: unauthorized file read or write outside the intended directory.

CVE-2026-45017 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.2.0); upgrading removes the vulnerable code path.

Kodem intelligence

The issue is fixed in version 2.2.0 with the inclusion of a template_path.is_absolute() condition in liquid/builtin/loaders/file_system_loader.py.

        if os.path.pardir in template_path.parts or template_path.is_absolute():
            raise TemplateNotFoundError(template_name)

1. What is CVE-2026-45017? CVE-2026-45017 is a high-severity path traversal vulnerability in python-liquid (pip), affecting versions < 2.2.0. It is fixed in 2.2.0. Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files.
2. How severe is CVE-2026-45017? CVE-2026-45017 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of python-liquid are affected by CVE-2026-45017? python-liquid (pip) versions < 2.2.0 is affected.
4. Is there a fix for CVE-2026-45017? Yes. CVE-2026-45017 is fixed in 2.2.0. Upgrade to this version or later.
5. Is CVE-2026-45017 exploitable, and should I be worried? Whether CVE-2026-45017 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-45017 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-45017? Upgrade python-liquid to 2.2.0 or later.