Hacking Humans – “Private Network Access (PNA) (noun) [Word Notes]”

Podcast: Hacking Humans (N2K Networks)
Date: November 11, 2025
Theme: Deception, influence, and social engineering in the world of cyber crime, with a focus on the new browser technology: Private Network Access (PNA).

Episode Overview

This Word Notes episode spotlights Private Network Access (PNA), an emerging browser configuration that aims to strengthen security by blocking unauthorized attempts to reach internal network resources from the open web. The hosts break down the reasoning, deployment, and implications of PNA, emphasizing its role in preventing social engineering and cyber attacks that exploit browser access weaknesses. The conversation references Google's implementation and the technical nuances developers need to consider.

Key Discussion Points & Insights

1. Definition and Function of PNA

• What is PNA?
  • A browser control that prevents browsers from accessing resources within private networks, unless specific security conditions are met.
• Example usage:
  • Chrome is "deprecating access to private network endpoints from non secure websites as part of the Private Network Access specification." ([01:56])

2. Background and Motivation

• CORS Protocol Rollout by Google:
  • Chrome introduced Cross-Origin Resource Sharing (CORS) in early 2022 to shield users from cross-site request forgery (CSRF) attacks, particularly those targeting private network devices like home routers.
  • Quote:
    • “The CORS goal is to protect users from cross site request forgery attacks or CRF attacks targeting routers and other devices on private networks.” ([02:13])
• Intended Protection:
  • Prevents compromised websites from reaching into users’ local networks (e.g., home routers, printers) unless specific permissions are granted.

3. Technical Details & Developer Impact

• Who is Affected?
  • Requests from public IPs to private IPs/localhost and requests from private IPs to localhost may be blocked unless allowed.
  • Potential Future Changes:
    • This specification could eventually expand to cover all cross-origin requests to private networks.
    • Quote:
      • "This may change to cover all cross origin requests to the private network in the future." ([03:12])
• Developer Adjustments:
  • Web applications within an IFRAME accessed over local networks, such as through VPNs, may encounter issues, especially if the user-facing app is hosted on public IPs.
  • Quote:
    • “If, however, your application is included in an IFRAME and accessed through your local Internet like your VPN, you might run into problems with Chrome.” ([03:34])

4. Security Implications and Real-World Example

• Nerd Reference Segment:
  • Daniel Laurie (IT Pro TV, Jan 2022) elaborates on what PNA addresses:
    • Prevents malware from using browsers as a bridge into users’ local environments, e.g., by blocking access to vulnerable routers.
    • Quote:
      • “What they're trying to implement is a new protocol to stop malware from reaching inside of your own home personal network and accessing resources there. That's what this is all about. So it is a security bump...” ([03:56])
    • Details of protocol: If a site tries to access internal resources (e.g., a router at 192.168.0.1), that attempt will be blocked unless explicitly allowed.
    • Quote:
      • “…it will say if I receive a request for an internal resource, it must first pass the test that we allow that type of thing. If it doesn't, which by default nothing will, then it won't allow access into those resources.” ([04:29])

Notable Quotes & Memorable Moments

• On the CORS protocol’s purpose:
  • "The CORS goal is to protect users from cross site request forgery attacks or CRF attacks targeting routers and other devices on private networks." (Speaker B, [02:13])
• On the changes developers may face:
  • "If, however, your application is included in an IFRAME and accessed through your local Internet like your vpn, you might run into problems with Chrome." (Speaker B, [03:34])
• On the essence of PNA’s security function:
  • "What they're trying to implement is a new protocol to stop malware from reaching inside of your own home personal network and accessing resources there. That's what this is all about. So it is a security bump..." (Daniel Laurie, [03:56])
  • "If it doesn't, which by default nothing will, then it won't allow access into those resources." (Daniel Laurie, [04:32])

Timestamps for Important Segments

• 01:34 — Introduction to PNA and browser security context.
• 02:13 — Explanation of CORS and its security rationale.
• 03:12 — Details about request restrictions and future expansion of the spec.
• 03:34 — Developer impacts and IFRAME example.
• 03:56 - 04:32 — Daniel Laurie’s security-focused explanation of PNA.

Tone and Style

The episode maintains a clear, educational tone with accessible explanations, utilizing real-world analogies (home routers, malware) and concrete developer scenarios. The references to browser technologies are up-to-date and practical, ensuring relevance for technical and non-technical listeners alike.

Summary

This episode provides a concise yet detailed primer on Private Network Access (PNA)—a browser security enhancement designed to thwart cyber criminals leveraging web browsers to infiltrate private networks. With historical background, technical specifics, and projected impacts on developers and end-users, the hosts clarify how PNA will both improve security and necessitate changes to web application architectures. The discussion anchors these concepts in familiar security and social engineering threats, making the technical content approachable for all listeners.