February 12, 2024

How to Secure PDFs with Encryption Using a Password Step-by–Step in 2024

PDFs are a great way to share documents. They are perfect to read and share information from anywhere, are compatible with almost all devices and operating systems, and can be an excellent way to organize sensitive and large chunks of information.

Despite their ubiquity and ease of use, PDFs remain highly vulnerable files susceptible to various cyber attacks. Their widespread usage makes them prime targets for malicious actors looking to exploit vulnerabilities and gain unauthorized access to sensitive information.

One common method is embedding malware into PDF files, which can then be unwittingly downloaded and executed by unsuspecting users. This poses a significant threat to the security and integrity of both personal and business data, highlighting the importance of implementing robust encryption and password protection measures.

In this blog post, let’s look at how PDFs are hacked and how you can enhance the security of your PDF documents by encrypting them with a password. Encrypting your PDFs adds an extra layer of protection by requiring a password to open and access the contents of the file. This simple yet effective security measure can help safeguard your sensitive information from unauthorized access and ensure that only intended recipients are able to view and use the document.

Vulnerabilities of PDF Files

Malware Embedding: Cybercriminals often exploit PDF files by embedding malware within them. These malicious files can be disguised as legitimate documents and distributed via email or file-sharing platforms. Once opened, the malware can infect the user's device, leading to data breaches or system compromise.

Phishing Attacks: PDF files are commonly used in phishing attacks, where attackers trick users into clicking on malicious links or downloading infected attachments. These phishing PDFs may appear to be legitimate documents from trusted sources, making them difficult to identify as threats.

Exploitable Security Flaws: PDF reader software and the PDF format itself may contain security vulnerabilities that can be exploited by attackers. These flaws could allow attackers to bypass security controls, execute arbitrary code, or gain unauthorized access to sensitive information stored within PDF files.

Password Weaknesses: Password-protected PDF files are only as secure as the strength of their passwords. Weak or easily guessable passwords can be cracked using brute-force attacks, allowing attackers to gain unauthorized access to the contents of the PDF.

Metadata Leakage: PDF files can contain hidden metadata that may inadvertently disclose sensitive information about the document or its author. This metadata could include details such as author names, creation dates, or revision history, which could be exploited by attackers for social engineering or targeted attacks.

Different Protection Methods for PDF Files

Encryption: One of the most effective ways to secure PDF files is by encrypting them with a password. Encryption scrambles the content of the PDF, making it unreadable without the correct password. This prevents unauthorized users from accessing the document's contents, even if they gain access to the file.

Access Controls: PDF files can be protected with access controls that restrict who can view, edit, or print the document. Access control settings can specify user permissions, such as allowing only certain users to view the document while preventing others from viewing or opening it

Redaction: Redaction is the process of permanently removing sensitive or confidential information from a PDF document. This can include text, images, or other content that should not be disclosed to unauthorized parties. Redaction tools allow users to selectively remove or obscure sensitive information before sharing the document. While it can remove sensitive information, it's not a good choice when you actually want to share sensitive information

Secure File Transfer: When sharing PDF files, it's essential to use secure file transfer methods to prevent interception or unauthorized access during transmission. Secure file transfer protocols, such as SFTP or HTTPS, encrypting data at rest before sharing it, ensuring that it remains secure from prying eyes.

How to Protect PDF Files With AxCrypt’s Encryption Software

Encryption is a powerful method for safeguarding sensitive PDFs, ensuring that they’re protected at all times. Encryption is different from other security methods such as password protection. Encryption transforms the contents of the PDF files into an unreadable and undecipherable format using algorithms and crypto keys, so that they cannot be read and made sense of by unauthorized users.

By encrypting your PDFs, you can be rest assured that they are protected at all times, even if someone gets access to them, as they will not be able to decrypt or read the contents of the PDFs without the decryption key. AxCrypt is a comprehensive file encryption software that protects your PDFs with the strongest and practically unbreakable encryption algorithm, the AES-256.

Follow these steps to encrypt your PDFs with passwords on Windows and Mac.

Video Tutorial:

STEP 1: Download and install AxCrypt

STEP 2: Open AxCrypt and sign in or sign up with your email and password.

STEP 3: Click the ‘Secure’ button with a padlock icon and select the file you’d like to encrypt.

STEP 4: This will encrypt the file and you can open it by either double-clicking the file on the ‘Recent Files’ tab or by clicking on ‘Open Secured’ and selecting the file.

STEP 5: To automatically encrypt, click on the File > Options and check the ‘Include Subfolders’ option.

STEP 6: Click on the ‘Secured Folders’ tab and right-click to add the desired folder that you would like to automatically encrypt files within.

STEP 7: Create, modify, add, or drag files to the secured folder and AxCrypt will automatically encrypt them once you click the ‘Cleanup’ button on the top-right or sign out of the application.

Your most recent encrypted files will appear on the main screen on the ‘Recent Files’ tab, and will have a file extension of .axx. You can add new folders and subfolders and AxCrypt will automatically encrypt the files within the folders.

To completely decrypt the file, click on the ‘Stop Securing’ icon from the main menu strip on top and select the files that you’d like to decrypt.

Follow these steps to encrypt your PDFs with passwords on your Android and iPhone.

Video Tutorial:

Quick 3-step tutorial to encrypt files your Android and iOS smartphones:

STEP 1: Install AxCrypt from Google PlayStore or App Store and sign into your account.

STEP 2: Tap the ‘Secure’ button with a padlock icon and select ‘Phone’.

STEP 3: Browse and select the files that you’d like to encrypt. Tap and hold to select multiple files.

And that’s it! Your files will be encrypted with an .axx file extension, and will appear on the ‘Recent Files’ tab under the menu strip. To open a file, just tap on any of the listed files directly from the main screen, or tap the ‘Open Secured’ button and select a file. To permanently decrypt a file, tap on the ‘Stop Securing’ button and select the file that you’d like to decrypt that has the .axx file extension.

When you open a file to view or edit, it only creates a temporary decryption process, and any changes made to the file will automatically be re-encrypted.

AxCrypt can also automatically encrypt and sync files on your Windows and Mac, and on your Google Drive and OneDrive accountsOneDrive accounts, so that you can access and edit them on the go on your phone.


In conclusion, the importance of securing PDFs with encryption and passwords cannot be overstated in today's digital age. Despite their convenience and versatility, PDFs are vulnerable to cyber threats, making robust security measures essential. Encrypting PDFs with strong passwords adds an extra layer of protection, ensuring that sensitive information remains safe from unauthorized access.

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