How to Sanitize PDF

Q: What methods are available in IronPDF for sanitizing PDFs?

IronPDF offers methods like SanitizeWithBitmap and SanitizeWithSvg within the Cleaner class to sanitize PDFs. These methods help remove scripts and embedded objects by converting PDFs into images and back.

Q: How does the ScanPdf method enhance PDF security?

The ScanPdf method in IronPDF enhances security by checking PDFs for vulnerabilities using YARA rules. It can identify potential threats, helping to mitigate risks associated with malicious PDFs.

Chaknith Bin

Updated:June 22, 2025

Sanitizing PDFs is a crucial process with many benefits. Primarily, it enhances document security by removing potentially harmful elements like embedded scripts or metadata, thereby reducing the risk of exploitation by malicious entities. Additionally, it improves compatibility across different platforms by removing complex or proprietary elements, enhancing accessibility. By mitigating risks of data leakage and ensuring document integrity, sanitizing PDFs contributes significantly to overall security and trustworthiness in document management practices.

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First Step:

How to Sanitize PDF in C#

Download IronPDF Library from NuGet
Use the Cleaner class to sanitize PDFs in multiple ways
Scan the PDFs using the ScanPdf method
Provide a custom YARA file that meets the requirements
Receive the new sanitized PDF document

Sanitize PDF Example

The trick behind sanitizing a PDF is to convert the PDF document into a type of image, which removes JavaScript code, embedded objects, and buttons, and then convert it back to a PDF document. We provide Bitmap and SVG image types. The key differences of SVG from Bitmap are:

Quicker than sanitizing with a bitmap
Results in a searchable PDF
Layout might be inconsistent

:path=/static-assets/pdf/content-code-examples/how-to/sanitize-pdf-sanitize-pdf.cs

using IronPdf;

// Import PDF document
PdfDocument pdf = PdfDocument.FromFile("sample.pdf");

// Sanitize with Bitmap
PdfDocument sanitizeWithBitmap = Cleaner.SanitizeWithBitmap(pdf);

// Sanitize with SVG
PdfDocument sanitizeWithSvg = Cleaner.SanitizeWithSvg(pdf);

// Export PDFs
sanitizeWithBitmap.SaveAs("sanitizeWithBitmap.pdf");
sanitizeWithSvg.SaveAs("sanitizeWithSvg.pdf");

Imports IronPdf

' Import PDF document
Private pdf As PdfDocument = PdfDocument.FromFile("sample.pdf")

' Sanitize with Bitmap
Private sanitizeWithBitmap As PdfDocument = Cleaner.SanitizeWithBitmap(pdf)

' Sanitize with SVG
Private sanitizeWithSvg As PdfDocument = Cleaner.SanitizeWithSvg(pdf)

' Export PDFs
sanitizeWithBitmap.SaveAs("sanitizeWithBitmap.pdf")
sanitizeWithSvg.SaveAs("sanitizeWithSvg.pdf")

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Sanitize with Options

Aside from sanitizing the PDFs, IronPDF also allows us to sanitize the PDF along with ChromeRenderOptions, which enables modification of parameters such as margins, paper size, and paper orientation.

Both SanitizeWithBitmap and SanitizeWithSvg can take a second optional parameter, which is a ChromeRenderOptions object. Here's a brief example of setting the bottom target margin of the PDF to 50 px by setting the MarginBottom property to 50 px.

For a complete list of available options, please refer to here.

:path=/static-assets/pdf/content-code-examples/how-to/santize-pdf-sanitize-chrome-render-options.cs

using IronPdf;

// Customize Chrome render options
var options = new ChromePdfRenderOptions();

// Set bottom margin to 50 pixels
options.MarginBottom = 50;

// Import PDF document
PdfDocument pdf = PdfDocument.FromFile("sample.pdf");

// Sanitize with Bitmap with Chrome render options
PdfDocument sanitizeWithBitmap = Cleaner.SanitizeWithBitmap(pdf,options);

// Sanitize with SVG with Chrome render options
PdfDocument sanitizeWithSvg = Cleaner.SanitizeWithSvg(pdf,options);

// Export PDFs
sanitizeWithBitmap.SaveAs("sanitizeWithBitmap.pdf");
sanitizeWithSvg.SaveAs("sanitizeWithSvg.pdf");

Imports IronPdf

' Customize Chrome render options
Private options = New ChromePdfRenderOptions()

' Set bottom margin to 50 pixels
options.MarginBottom = 50

' Import PDF document
Dim pdf As PdfDocument = PdfDocument.FromFile("sample.pdf")

' Sanitize with Bitmap with Chrome render options
Dim sanitizeWithBitmap As PdfDocument = Cleaner.SanitizeWithBitmap(pdf,options)

' Sanitize with SVG with Chrome render options
Dim sanitizeWithSvg As PdfDocument = Cleaner.SanitizeWithSvg(pdf,options)

' Export PDFs
sanitizeWithBitmap.SaveAs("sanitizeWithBitmap.pdf")
sanitizeWithSvg.SaveAs("sanitizeWithSvg.pdf")

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Scan PDF Example

Use the ScanPdf method of the Cleaner class to check if the PDF has any potential vulnerabilities. This method will check with the default YARA file. However, feel free to upload a custom YARA file that meets your requirements to the second parameter of the method.

A YARA file for PDF documents contains rules or patterns used to identify characteristics associated with malicious PDF files. These rules help security analysts automate the detection of potential threats and take appropriate actions to mitigate risks.

:path=/static-assets/pdf/content-code-examples/how-to/sanitize-pdf-scan-pdf.cs

using IronPdf;
using System;

// Import PDF document
PdfDocument pdf = PdfDocument.FromFile("sample.pdf");

// Scan PDF
CleanerScanResult result = Cleaner.ScanPdf(pdf);

// Output the result
Console.WriteLine(result.IsDetected);
Console.WriteLine(result.Risks.Count);

Imports IronPdf
Imports System

' Import PDF document
Private pdf As PdfDocument = PdfDocument.FromFile("sample.pdf")

' Scan PDF
Private result As CleanerScanResult = Cleaner.ScanPdf(pdf)

' Output the result
Console.WriteLine(result.IsDetected)
Console.WriteLine(result.Risks.Count)

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Ready to see what else you can do? Check out our tutorial page here: Sign and Secure PDFs

Frequently Asked Questions

How can I sanitize a PDF in C#?

To sanitize a PDF in C#, use the IronPDF library's Cleaner class. This involves converting the PDF into an image format like SVG or Bitmap to remove harmful elements, and then converting it back to a PDF.

What methods are available in IronPDF for sanitizing PDFs?

IronPDF offers methods like SanitizeWithBitmap and SanitizeWithSvg within the Cleaner class to sanitize PDFs. These methods help remove scripts and embedded objects by converting PDFs into images and back.

What is the benefit of using SVG over Bitmap for PDF sanitization?

Using SVG for PDF sanitization is quicker and results in a searchable PDF. However, it might cause layout inconsistencies compared to using Bitmap.

How do I use a custom YARA file to scan PDFs?

To use a custom YARA file in IronPDF, pass the file as a second parameter to the ScanPdf method. This allows you to check for specific vulnerabilities based on custom security rules.

What is the role of the Cleaner class in PDF sanitization?

The Cleaner class in IronPDF is designed to sanitize PDFs by removing potentially harmful elements. It provides methods to convert PDFs into images, which helps in stripping away scripts and embedded objects.

Can I modify document parameters during PDF sanitization?

Yes, you can modify document parameters during PDF sanitization using IronPDF's ChromeRenderOptions. This allows changes to margins, paper size, and orientation.

How does the ScanPdf method enhance PDF security?

The ScanPdf method in IronPDF enhances security by checking PDFs for vulnerabilities using YARA rules. It can identify potential threats, helping to mitigate risks associated with malicious PDFs.

Why is PDF sanitization important?

PDF sanitization is crucial for enhancing document security by removing harmful elements like scripts or metadata. It reduces exploitation risks, improves compatibility, and ensures document integrity.

Chaknith Bin

Chat with engineering team now

Software Engineer

Chaknith works on IronXL and IronBarcode. He has deep expertise in C# and .NET, helping improve the software and support customers. His insights from user interactions contribute to better products, documentation, and overall experience.