# 4.4 HTTP Header Filtering

#### 📘 Overview

The **HTTP Header Filtering** module allows you to filter incoming HTTP requests based on the **name and value** of specific HTTP headers.\
This is useful for blocking or allowing requests based on exact or expected header content.

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#### 🛠️ How It Works

You can define a simple rule by providing:

* A **Header Title** (e.g., `Origin`, `Authorization`, `X-Custom-Header`)
* A **Header Content** (exact match string)

Once the rule is created, incoming requests will be matched against this rule and **filtered accordingly**.

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#### ⚙️ How to Add a Header Filter

1. Go to **Security Rules > HTTP Header Filtering**
2. Click **Create Header Filtering**
3. Fill out:
   * `Enter Header Title`
   * `Enter Header Content`
4. Click **Filter**
5. The rule will take effect immediately

<figure><img src="/files/BdUr9N1xw6KmcDaxHNzp" alt=""><figcaption></figcaption></figure>

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#### 🔐 Why It Matters

Many attacks exploit improperly validated or missing headers, including:

* CSRF attacks (missing Origin / Referer headers)
* Host Header Injection
* API key misuse

Header filtering adds a layer of control at the gateway level to prevent such attacks early.

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🎯 **HTTP Header Filtering is a quick way to enforce header presence and exact values, adding lightweight security to your application endpoints.**


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