How to Sanitize PDF

by Chaknith Bin

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.

C# NuGet Library for PDF

Install with NuGet

Install-Package IronPdf

Download DLL

Download DLL

Manually install into your project

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
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
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
VB   C#

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.

using IronPdf;
using System;

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

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

// Output the result
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
VB   C#

Chaknith Bin

Software Engineer

Chaknith is the Sherlock Holmes of developers. It first occurred to him he might have a future in software engineering, when he was doing code challenges for fun. His focus is on IronXL and IronBarcode, but he takes pride in helping customers with every product. Chaknith leverages his knowledge from talking directly with customers, to help further improve the products themselves. His anecdotal feedback goes beyond Jira tickets and supports product development, documentation and marketing, to improve customer’s overall experience.When he isn’t in the office, he can be found learning about machine learning, coding and hiking.