> For the complete documentation index, see [llms.txt](https://docs.sec1.io/user-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.sec1.io/user-docs/4-sast/3-javascript/unsanitized-user-input-in-deserialization-method.md).

# Unsanitized user input in deserialization method

## Overview

* **Rule ID**: `javascript_express_unsafe_deserialization`
* **Applicable Languages**: Javascript
* **Weakness ID**: CWE-502

## Description

Deserializing untrusted data exposes your application to security risks. This vulnerability arises when data, particularly from external sources like request objects, is deserialized without proper sanitization. Attackers can embed malicious code or payloads in serialized data, which can compromise your application's security upon deserialization.

## Remediation Guidelines

* **Do not** deserialize data from untrusted sources directly. This practice can lead to security vulnerabilities by executing malicious code embedded in the data.
* **Do use** data-only, language-agnostic serialization formats such as JSON or XML for deserializing data. These formats are less susceptible to manipulation by attackers aiming to exploit the deserialization process.

  ```java
  JSON.parse(req.params);
  ```

## References

* [**OWASP Deserialization cheat sheet**](https://cheatsheetseries.owasp.org/cheatsheets/Deserialization_Cheat_Sheet.html)
* [**CWE-502: Deserialization of Untrusted Data**](https://cwe.mitre.org/data/definitions/502.html)
* [**OWASP Top 10: A08:2021 - Software and Data Integrity Failures**](https://owasp.org/Top10/A08_2021-Software_and_Data_Integrity_Failures/)

## Configuration

To omit this rule during a scan, and to provide you with continuous 24/7 code-level scanning, you can employ our [**SAST TOOL**](https://scopy.sec1.io/login)


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