External risk intelligence

Langchain PALChain Code Execution Vulnerability.

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2023-36095

LangChain is a software library framework used within custom application code. While applications built using LangChain may be deployed as internet-facing services, the library itself is a development component rather than a pre-packaged edge service, gateway, or standalone appliance. Exposure depends entirely on how a developer integrates and deploys the framework.

Code Injection

Langchain

0.0.194

Halo Surface Signal: 3 out of 5 — possibly public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

An issue was identified in a software library used for developing applications, specifically related to how it handles certain code execution commands. This vulnerability could allow an unauthorized party to run their own code on a system if the affected library is integrated into an application and that application is then exploited. The primary concern at this level is to determine if this specific library is in use within our organization's technology landscape.

Software library allows attackers to run unauthorized code.
Leadership should track risks related to software development components.
Confirm if this library is used in our applications.

Attack Path

How an attacker could exploit the issue

An attacker with network access could potentially reach the vulnerable component by interacting with a system that uses the affected version of the langchain library. The vulnerability lies in the library's handling of Python `exec` calls within specific functions, which, when triggered by malicious input, can lead to arbitrary code execution.

Entry Condition: Unauthenticated network access.
Trigger Point: Malicious input to specific functions.
Resulting Risk: Arbitrary code execution.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability could allow an attacker to execute arbitrary code by leveraging insecure Python `exec` calls within specific functions of the langchain library. This could occur when an application uses these functions in a way that allows an attacker to influence the code being executed.

Arbitrary code execution.
Malicious input to affected functions.
System compromise or data alteration.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability impacts custom applications developed using the LangChain framework, specifically those incorporating the PALChain component with affected functions. Application owners, in coordination with platform or development teams, should first confirm the presence and reachability of vulnerable LangChain versions within their deployed codebases. Subsequently, an exposure review and risk assessment will inform prioritized remediation planning, potentially involving vendor consultation if the framework is integrated via a third-party solution.

Application owners should own the issue.
Verify vulnerable LangChain versions are used.
Plan remediation based on exposure risk.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

Free EASM Trial See How Signal Works

Frequently asked questions

What is the langchain library?

Langchain is a development framework designed to help software engineers build applications that leverage large language models. It provides modular components and tools to connect these models to various data sources and workflows. Because it is a library rather than a standalone product, it is embedded directly into custom software to add intelligent features, meaning its functionality—and any associated risks—depends on how a developer implements it.

What does CWE-94 mean for CVE-2023-36095?

CWE-94 refers to improper control of generation of code, often called code injection. In the context of CVE-2023-36095, this weakness exists because the library uses the Python 'exec' function to process data. If an application provides an untrusted user the ability to influence the input sent to specific functions within the PALChain component, the software may inadvertently treat that malicious input as executable commands, granting the attacker control over the system.

How can an attacker trigger this vulnerability?

An attacker triggers this issue by providing specially crafted, malicious input to affected functions within the PALChain component, such as from_math_prompt. This does not happen automatically; the vulnerability is only reachable if your application design accepts external input and passes it directly into these specific functions without sufficient sanitization. If your code does not use these specific PALChain features, or if inputs are strictly validated, this trigger path is not active.

Do I need to worry about this vulnerability?

You should investigate if your custom applications use the affected version (0.0.194) of the langchain library. According to Halo Surface Signal, because this is a development component integrated into custom code rather than a pre-packaged appliance, relevance depends entirely on your specific deployment. If your application exposes features using the vulnerable PALChain functions to the internet, the risk of unauthorized access is higher than if the code runs in an isolated environment.

How do I respond to CVE-2023-36095?

Your first step is to perform a software inventory to identify if version 0.0.194 is present in your codebases. Because this is a library, you should coordinate with your development teams to confirm whether the affected PALChain functions are actively used. If they are, prioritize reviewing how those functions handle input and consult the library maintainers for official updates or secure alternatives to replace the insecure code execution pattern.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.