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PDF Security Guide
Hidden Threats & Prevention

PDFs are not just simple documents. They can hide threats like JavaScript, auto-execute actions, and phishing links. This guide covers the hidden dangers in PDFs and how to prevent them.

5 Hidden Threats in PDFs

PDF files don't just contain text and images. They can include various executable code and external connections.

Danger

JavaScript Execution Code

PDFs can contain JavaScript. Simply opening the file can trigger malicious scripts to execute.

Danger

Auto-Execute Actions

Hidden actions in PDFs can automatically connect to external URLs or launch programs when the file is opened.

Warning

Phishing Links

Fake links that look like legitimate URLs but actually redirect to phishing sites can be embedded in PDFs.

Warning

Hidden Metadata

Sensitive personal information like author names, GPS locations, and revision history can remain in PDF metadata.

Warning

Form Data Collection

Input forms within PDFs can automatically transmit entered data to external servers.

Real Attack Cases

Credential Theft via Email PDF Attachments

PDF invoices disguised as messages from business partners redirect victims to fake login pages, stealing account credentials.

Malicious Scripts Hidden in Resume PDFs

Attackers target recruiters by embedding malicious JavaScript in resumes. Opening the PDF triggers automatic malware execution.

Phishing Links in Official Document Disguises

PDFs disguised as government or bank documents contain phishing links designed to trick users into entering personal information.

PDF Security Checklist

  1. Don't open PDFs from unknown sources. Never open PDF attachments from emails where you cannot verify the sender.
  2. Keep your PDF viewer updated. Using the latest viewer with security patches blocks known vulnerabilities.
  3. Disable JavaScript execution. Turn off JavaScript execution in PDF viewers like Adobe Acrobat.
  4. Scan before opening. Check suspicious PDFs with a security scanning tool before opening them.
  5. Remove threats with IMGLOO PDF Cleaner. Upload a PDF to IMGLOO to automatically detect and remove malicious scripts, phishing links, and auto-actions.

How to Scan PDFs with IMGLOO

Remove PDF threats right in your browser without installing anything.

  1. 1

    Upload PDF File

    Drag and drop or select the PDF file you want to scan.

  2. 2

    Auto Threat Detection & Removal

    Automatically detects and safely removes threats like JavaScript, auto-execute actions, and phishing links.

  3. 3

    Download Safe PDF

    Download the cleaned PDF with all threats removed. All processing happens in your browser.

Scan Your PDFs for Security Now

No installation, no signup. Right in your browser.

Use PDF Cleaner

Frequently Asked Questions

Can PDFs contain viruses?+

Yes. PDFs can contain JavaScript, auto-execute actions, and external URL connections. While not traditional viruses, they can cause harm through phishing or malicious script execution.

How does IMGLOO PDF Cleaner work?+

It detects and safely removes threat elements like JavaScript, OpenAction, and URIs inside PDFs. Normal content like text and images remains intact.

Are my files uploaded to a server?+

No. IMGLOO processes everything in your browser. Your PDF files are never sent to any external server, so you can safely scan confidential documents.

Can it remove all threats?+

IMGLOO removes major threats including JavaScript, auto-execute actions, phishing links, and external connections. For advanced attacks targeting PDF structure vulnerabilities, we recommend using specialized security tools alongside.

Is it free?+

Yes, IMGLOO PDF Cleaner is free to use. No signup required.