How Does PGP Encryption Work—and Is It Still Secure in 2025?

What Is PGP Encryption?

One of the most enduring tools in the fight to protect sensitive data is Pretty Good Privacy (PGP), a foundational method for email encryption and file protection. It’s a protocol that has stood the test of time since it was first developed in 1991, even as surveillance tools and programs have grown increasingly widespread around the globe.

More than three decades later, its core cryptographic principles remain solid. But is it still relevant in 2025? And what risks, limitations, or evolutions should users understand today?

Let’s unpack how PGP encryption works, where it excels, where it falls short, and how organizations can use it.

How PGP Encryption Works

To understand PGP’s lasting appeal, it’s helpful to look at how it balances speed and security through a hybrid encryption model rooted in public key cryptography.

PGP uses a combination of symmetric encryption and asymmetric methods:

• • Session key generation: PGP generates a random session key
  • Session key encryption: This session key is encrypted with the public key of the recipient

• Transmission and decryption: The sender transmits the encrypted message and session key to the recipient, who decrypts it with their private key

• Message receipt: The recipient uses the random session key to decrypt the message sent

This process can be slower than other encryption methods. But this layered method ensures end-to-end encryption, where only the intended recipient with the correct private key can access the message.

Why PGP Still Matters in 2025

Despite its age, PGP in 2025 remains a critical component of privacy-first communications. It delivers:

• Strong end-to-end encryption to protect sensitive communications
• Authentication via digital signatures, verifying message origin

Its decentralized model and resistance to mass surveillance continue to make it essential for journalists, developers, privacy advocates, security-focused professionals, or anyone security-minded.

Other Encryption Methods

What Makes PGP Different from SSL/TLS?

PGP encrypts data at rest and during transmission between users, offering sender-to-recipient protection. SSL/TLS (Secure Sockets Layer / Transport Layer Security) encrypts data in transit across networks but does not protect content once it arrives. This makes PGP more resilient for stored or archived information.

What are other encryption options?

Several modern solutions or applications aim to deliver encryption that some may find have better usability than PGP. These tools don’t fully replace PGP but can provide more streamlined alternatives for many users:

• Sigal is an end-to-end encrypted messaging platform powered by open source code
• ProtonMail, which supports use of PGP, and Tuta (Tutanota), which does not use PGP, provide email encryption options

When Should You Still Use PGP?

Despite its drawbacks, PGP remains a go-to solution for:

• Secure communications between researchers, journalists, engineers, and security professionals
• Sending and receiving encrypted emails
• Protecting and encrypting files at rest
• Digital signature verification 

Its transparency, decentralization, and continued resistance to surveillance make it relevant in niche but important scenarios.

Final Thoughts

Through its Attack Surface Intelligence (ASI) platform, SecurityScorecard continuously monitors for exposed credentials, expired certificates, and poorly configured encryption protocols. Our data includes more than 3.9 billion IPs scanned approximately every seven days across over 1,400 ports, surfacing real-world encryption gaps.

This visibility allows teams to:

• Detect domains with improperly published cryptographic keys
• Assess email-related encryption posture based on public DNS and TLS artifacts

Ensuring proper encryption practices is a business continuity concern. SecurityScorecard’s telemetry can bring proactive clarity to an often-invisible risk layer.

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