A PDF, or Portable Document Format, is a file developed by Adobe in the 1990s to present documents in a way that preserved the fonts, layout, and graphics of the original document without being susceptible to incompatibility issues of multiple, other software systems that could misread the document. 

Ideally, a PDF is a static document, formatted to retain its information, including text, fonts, vector graphics, images, hyperlinks, and other information needed to display it. PDF was standardized in 2008, and no longer requires Adobe royalties for its use.

With all of that permanent layout, its easy to expect PDFs to be secure, but are they really? In this age when PDFs are used to capture important information, such as personally identifiable information from individuals or tax or financial information from companies, we need PDFs to be as secure as possible. 

So how can this be done?


Is Sending PDFs Via Email Really Secure?

Sending an email is like sending a postcard: everyone or every system that handles it can see and record what you’ve written, and when you send an email it doesn’t just fly straight from your computer to your receiver’s computer; indeed, there are a lot of short but critical pauses along the way. 

Unfortunately, ePDFs sent through email or uploaded to websites and apps can be intercepted by cybercriminals and read if the PDFs are not encrypted. Users would need to incorporate additional security measures to their work or home systems, including adding two-factor authentication (2FA) to their devices and apps, using a firewall or VPN, or updating their home Wi-Fi’s router firmware and security level.


How to Password Protect a PDF

Adding a password is the first and most basic method of securing a PDF, and in many cases it’s all that you need. 

Adobe offers a way to password-protect a PDF. You can do it within the Adobe Acrobat software (Tools > Protect > Encrypt > Encrypt with Password) or by simply uploading a PDF to the Adobe website and choosing a password. 

When you use this  Acrobat online tool to add password protection to a PDF file, it encrypts the file for added security. Encryption turns document content into unreadable cipher text, and only authorized users who have the password can decrypt the document. 

The good news is that encryption can thwart cybercriminals who may attempt to capture the PDF document in transit, such as by diverting Internet traffic, as the encrypted PDF will be unreadable.

Adobe has added other features to strengthen the security of PDF documents. The Redact feature allows users to permanently delete sensitive text, graphics, or hidden data from a PDF document. This can keep confidential information hidden, even though the rest of the document, including signatures, would be visible.


Shortcomings of Password Protecting PDFs

A password can prevent people from altering a PDF, but it doesn’t provide complete protection if people wish to share it.

For example, someone might send you a password-protected PDF, but also send the password with it. This essentially defeats the purpose of password protection, since that email can potentially be forwarded to countless other people. Even worse, someone might share the PDF and the password online or via social media.

As such, the password protection of PDFs, even if the document might be encrypted, does not offer enough security, which can be an issue in the case of highly-sensitive material.


Using a VDR to Securely Share Sensitive PDFs

It’s clear that email is not safe enough when it comes to ensuring that your PDFs are protected when sharing them with third parties. That is where a virtual data room like CapLinked comes into play. 

CapLinked’s world-class platform allows for thousands of documents of all types (PDFs, included) to be uploaded to an ultra-secure digital workspace where administrators can set detailed permissions for who can view, download, and edit documents and data.  

Using the centralized hub for all Caplinked activity, the dashboard, you are able to access all workspaces, view recent activity, monitor notifications, and manage contacts and messages from a user-friendly interface. Caplinked can be used anywhere, from any device on any platform. 

Here’s how a CapLinked VDR allows you to securely share PDFs.


Step 1: Workspaces

Workspaces serve as a secure vault for sharing documents and PDFs. Setup takes less than ten minutes, it has unrivaled file and folder upload speeds, and you can manage and access all your Workspaces from your desktop or mobile device.


Step 2: Document Control and Management

Quickly upload documents directly from your browser or use Caplinked’s powerful desktop uploader, Safelink. Then harness the document editing power of Microsoft Office to make changes directly from your Workspace. From there you can view PDFs, Microsoft Office files, images, and video directly from your browser without any additional plugins for downloads. 

You can update copy, make additions for Excel and Word documents all within the Safelink system, as well as tracking any changes made to a document. Here is where you can add further protection by redacting or blocking out sensitive information that will not be necessary for evaluation on the Workspace.

An example of this might be with the uploading of PDFs of bank statements; while records of transactions are important, the account numbers are not and can be removed before sharing.

After editing your document, Caplinked creates a new version of the file on our secure server. This is critical for security, as only this new Caplinked version will be the version shared among authorized users in the Workspace—not the originally uploaded document. 


Step 3. Collaboration

Rather than just collaborating with a wide variety of people all using the same password, Caplinked’s editing and collaboration tools make communication with teammates and external parties simple and easy. 

Store, edit, and correspond on a secure Workspace without downloading countless files. When changes are made, send messages to stakeholders through Update Announcements. Internally collaborate with collaborators using instant messaging. Q&A Assignments (also known as Subject Matter Experts) let you assign one of multiple administrators to answer questions from a specific permission group. And a comprehensive activity feed keeps administrators up to date and alert to any changes made to the document.


Step 4: Permissions

You can create customizable groups and configure view, download, and upload permissions for all documents or individual folders and files. Link your Salesforce or Caplinked contacts to add hundreds of users directly to custom groups. All files are private by default, and you can immediately revoke access to workspaces or files whenever you choose.


Step 5: Track Changes

Track all actions and changes made within a Workspace including views, downloads, permissions changes, and viewed pages. This enables you to maintain a comprehensive audit trail of every edit, action, or event that occurs within a Workspace. You can quickly locate earlier versions of a file in case something was improperly modified, and you can generate detailed reports using custom filters to keep your team, external collaborators, and investors on the same page.


Step 6: Digital Rights Management

FileProtect provides a secure digital rights management (DRM) wrapper around your sensitive files, protecting documents against vulnerabilities and hacks. Viewers must log in with secure credentials to open the file, keeping the file protected after downloaded. You can grant or restrict access to viewing or printing documents at any time, and you can revoke rights at any time without worrying about the security of your files.


Step 7: Watermarking

You can enhance sharing documents by watermarking them with Caplinked watermarking. Apply custom watermarks that include time, date, email, and IP address.


Step 8: Security

Finally, your documents are protected with the industry’s most secure technology and credentials. Plugin-free technology means no more worrying about software updates or threats. We use military-grade 256-bit encryption, SSAWE18 and ISO 27001 certified servers, and are HIPAA and SOC 2 Compliant. Only Workplace administrators decide who gets access to each document and whether or not those with access can view, edit, download, and/or upload documents.


Start your free trial today to see how CapLinked can help streamline all aspects safely and securely sharing the sensitive PDFs your business needs to close deals and win customers. 

Jake Wengroff writes about technology and financial services. A former technology reporter for CBS Radio, he covers such topics as security, mobility, e-commerce and the Internet of Things.