# Leakage of Sensitive Information in Exception Messages

## Overview

* **Rule ID**: `javascript_express_cookie_missing_http_only`
* **Applicable Languages**: Javascript
* **Weakness ID**: CWE-1004

## Description

If the HTTP Only option is not configured, your cookies are at risk. This setting is essential because it prevents client-side JavaScript from accessing cookie values through code like "document.cookie". Enabling HTTP Only is crucial for websites vulnerable to Cross-Site Scripting (XSS) attacks, as it stops malicious scripts from obtaining cookie data.

## Remediation Guidelines

* **Set** the HttpOnly attribute to true in your cookie configuration. This ensures that cookies are protected from unauthorized client-side access.

  ```java
  cookie({ httpOnly: true });
  ```

## References

* [**Express Security Best Practices**](https://expressjs.com/en/advanced/best-practice-security.html#use-cookies-securely)
* [**CWE-1004: Sensitive Cookie Without 'HttpOnly' Flag**](https://cwe.mitre.org/data/definitions/1004.html)
* [**OWASP Top 10: A05:2021 - Security Misconfiguration**](https://owasp.org/Top10/A05_2021-Security_Misconfiguration/)

## 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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