Why Your Next Aviation Pentest Needs a VDP Strategy

TLDR: Aviation systems like Electronic Flight Bags (EFBs) are increasingly connected, yet they often lack the mature vulnerability disclosure processes found in web applications. This talk breaks down the friction between security researchers and aviation OEMs, showing why "security by obscurity" is failing in the face of modern connectivity. Pentesters should focus on identifying these disclosure gaps early in their engagements to avoid legal and professional dead-ends.

Aviation security is currently stuck in a transition period. We are moving from isolated, proprietary hardware to connected, data-heavy environments, but the industry’s response to vulnerability reporting remains trapped in the past. When you find an authentication bypass in an Electronic Flight Bag (EFB) or an avionics interface, you are not just dealing with a software bug. You are entering a minefield of regulatory compliance, safety-critical concerns, and manufacturers who often view "vulnerability" as a dirty word.

The Reality of Disclosure in High-Stakes Environments

Most researchers in the web space are used to the OWASP Vulnerability Disclosure Cheat Sheet as a baseline. You find a bug, you report it, you get a bounty or a CVE, and you move on. In aviation, that process is frequently broken. Manufacturers often default to "that is a feature, not a bug" or simply ignore reports because they lack a formal Vulnerability Disclosure Program (VDP).

The core issue is that aviation OEMs are terrified of the safety implications. If you report an authentication bypass that could theoretically allow an attacker to modify flight data, the manufacturer’s legal team often panics. They do not see a researcher helping them; they see a liability. This leads to the "stone-walling" effect, where researchers are ignored for months or threatened with legal action, even when the research is conducted in good faith.

Why Authentication Bypass is the New Normal

Electronic Flight Bags are essentially tablets running specialized software that replaces paper charts and flight manuals. They are increasingly integrated with aircraft systems, meaning they are no longer just static document viewers. When these devices are poorly configured, they become prime targets for authentication bypass attacks.

If you are performing a pentest on an EFB or related aviation software, look for the standard suspects: hardcoded credentials, insecure API endpoints, or weak session management. The mechanical reality of these bypasses is often trivial. For example, many of these systems rely on legacy protocols that assume a trusted network environment. If you can gain access to the local network or the device itself, you can often bypass authentication by manipulating the underlying service calls.

Consider a scenario where an EFB application communicates with a ground-based server. If the API lacks proper token validation, a simple request modification can grant you unauthorized access to sensitive flight data.

# Example of a basic API request that might be vulnerable
curl -X POST -H "Content-Type: application/json" -d '{"user": "admin", "bypass": "true"}' https://efb-api.example.com/v1/login

This is not rocket science, but it is high-stakes. The impact of such a vulnerability is not just data theft; it is the potential for unauthorized modification of flight-critical information.

Navigating the Legal and Professional Minefield

When you encounter these vulnerabilities, your approach matters more than your exploit. If you go straight to social media or a public disclosure platform, you will likely burn bridges and face legal pushback. The aviation industry is small, and your reputation is your most valuable asset.

Instead, treat the engagement as a long-term project. If the company has no VDP, look for a security contact or a CISO. If you cannot find one, consider reaching out to organizations like the Aviation ISAC, which acts as a clearinghouse for security information in the sector. They can often facilitate the conversation between researchers and manufacturers, providing a layer of professional insulation that protects both parties.

Remember that the 60-day or 90-day disclosure timelines common in bug bounty programs do not apply here. Aviation systems are complex, and patching a vulnerability might require a multi-year certification process. You are not just waiting for a code push; you are waiting for a regulatory sign-off.

The Defensive Shift

Defenders in the aviation space need to stop relying on security by obscurity. If your system is visible to the internet or connected to a broader network, it will be probed. The most effective defense is a transparent, well-documented VDP. If you are a developer or a security lead in this space, start by creating a security.txt file on your domain. It is a simple, low-effort step that signals to researchers that you are open to communication.

Furthermore, implement robust logging and monitoring. If you cannot prevent an authentication bypass, you must be able to detect it. Aviation systems should be treated as high-value targets, and that means applying the same rigor to their security as you would to a cloud-native web application.

Finally, do not use legal threats to silence researchers. It never works, and it only ensures that the next researcher who finds a bug will go straight to a public disclosure site instead of talking to you. If you are a researcher, keep your documentation clean, keep your communication professional, and always prioritize the safety of the systems you are testing. The goal is to make the industry better, not to win a short-term argument. If you find yourself in a position where you are being ignored, document your attempts to reach out and keep your findings secure. Eventually, you will find the right channel, and the industry will be safer for it.