high CVSS 7.5

CVE-2026-45017·Python vulnerability

Python Liquid is a Python engine for the Liquid template language. Prior to 2.2.0, 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. This vulnerability is fixed in 2.2.0.

Severity
high
Software
Python
Fixed in
2.2.0
Published
2026-05-28

Affected versions

Until: 2.2.0

Fixed in: 2.2.0

How to fix this CVE

Update Python Liquid to version 2.2.0 or later to patch the path traversal vulnerability in FileSystemLoader and CachingFileSystemLoader. If you use Python Liquid for template rendering, verify that your application only loads templates from designated directories and restrict absolute path resolution. After patching, test your template rendering pipeline to ensure no legitimate functionality is broken.

sudo dnf update python3-liquid

Defensia detects this vulnerability

How to check if you are affected

  1. Check Python Liquid version: python3 -c "import liquid; print(liquid.__version__)" or pip3 show liquid-template
  2. Identify applications using Python Liquid: grep -r "from liquid import" /opt /srv /home --include="*.py" 2>/dev/null or pip3 list | grep -i liquid
  3. Review template directories for suspicious include/render tags: grep -r "{% include" /path/to/templates --include="*.liquid" | grep -E "^/|\.\." to spot absolute or traversal paths
  4. Verify patch installation: python3 -m pip index versions liquid-template 2>/dev/null | head -20 and confirm installed version is >= 2.2.0

FAQ

What is CVE-2026-45017?

CVE-2026-45017 is a path traversal vulnerability in Python Liquid's template loaders that allows attackers to read and render arbitrary files from the server if an absolute file path is provided to the {% include %} or {% render %} tags, bypassing intended directory restrictions.

Is CVE-2026-45017 being actively exploited?

No, this vulnerability is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog and no public exploits are available. However, prompt patching is still recommended due to its high severity.

What versions of Python Liquid are affected by CVE-2026-45017?

All versions of Python Liquid prior to 2.2.0 are affected. Version 2.2.0 and later contain the security fix.

How do I check if my server is vulnerable to CVE-2026-45017?

Run `pip3 show liquid-template | grep Version` to check the installed version. If the version is below 2.2.0, your server is vulnerable.

Does Defensia detect CVE-2026-45017?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Python Liquid is installed on a monitored server, CVE-2026-45017 will appear in your dashboard with remediation steps.

Related Python CVEs

CVE-2026-28505CVSS 10Tautulli is a Python based monitoring and tracking tool for Plex Media Server. Prior to version 2.17.0, the str_eval() function in notification_handler.py implements a sandboxed eval() for notification text templates. The sandbox attempts to restrict callable names by inspecting code.co_names of the compiled code object. However, co_names only contains names from the outer code object. When a lambda expression is used, it creates a nested code object whose attribute accesses are stored in code.co_consts, NOT in code.co_names. The sandbox never inspects nested code objects. This issue has been patched in version 2.17.0.
CVE-2026-34938CVSS 10PraisonAI is a multi-agent teams system. Prior to version 1.5.90, execute_code() in praisonai-agents runs attacker-controlled Python inside a three-layer sandbox that can be fully bypassed by passing a str subclass with an overridden startswith() method to the _safe_getattr wrapper, achieving arbitrary OS command execution on the host. This issue has been patched in version 1.5.90.
CVE-2026-33054CVSS 10Mesop is a Python-based UI framework that allows users to build web applications. Versions 1.2.2 and below contain a Path Traversal vulnerability that allows any user supplying an untrusted state_token through the UI stream payload to arbitrarily target files on the disk under the standard file-based runtime backend. This can result in application denial of service (via crash loops when reading non-msgpack target files as configurations), or arbitrary file manipulation. This vulnerability heavily exposes systems hosted utilizing FileStateSessionBackend. Unauthorized malicious actors could interact with arbitrary payloads overwriting or explicitly removing underlying service resources natively outside the application bounds. This issue has been fixed in version 1.2.3.
CVE-2026-25632CVSS 10EPyT-Flow is a Python package designed for the easy generation of hydraulic and water quality scenario data of water distribution networks. Prior to 0.16.1, EPyT-Flow’s REST API parses attacker-controlled JSON request bodies using a custom deserializer (my_load_from_json) that supports a type field. When type is present, the deserializer dynamically imports an attacker-specified module/class and instantiates it with attacker-supplied arguments. This allows invoking dangerous classes such as subprocess.Popen, which can lead to OS command execution during JSON parsing. This also affects the loading of JSON files. This vulnerability is fixed in 0.16.1.
CVE-2026-9135CVSS 9.9IBM Langflow OSS 1.0.0 through 1.10.0 Langflow versions up to 1.9.2 (commit 94981c443d4918517b9e8163d70fc598dc33a32d) contain a code injection vulnerability in the Policies component's ToolGuard integration that bypasses the allow_custom_components=false security control. The vulnerability exists because the validation mechanism only checks the main component source code in node_template["code"]["value"] but fails to validate dynamic CodeInput fields that store generated ToolGuard Python files. Attackers can embed malicious Python code in these unvalidated dynamic fields, which are persisted in Flow.data and later executed server-side when a guarded tool is invoked through the ToolGuard runtime. This allows authenticated users with flow creation privileges to achieve arbitrary Python code execution on the backend despite custom component restrictions. The vulnerability can be escalated through cross-tenant flow manipulation via the agentic MCP update_flow_component_field tool, which accepts attacker-controlled user_id parameters, enabling attackers to inject malicious code into victim users' flows. When combined with publicly accessible flows and specific misconfigurations (AUTO_LOGIN=true, NEW_USER_IS_ACTIVE=true), the attack can be conducted with reduced authentication requirements.

References

Track CVEs across your fleet automatically

Defensia scans your Linux servers and tells you exactly which ones are running vulnerable versions — including CVE-2026-45017. Free for 1 server.

Get started free