Solved: Desktop Application Security Verification Standard – DASVS

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🚀 Executive Summary

TL;DR: The desktop application security landscape lacks a consistent verification standard (DASVS) due to platform, language, and attack surface fragmentation, making assessments challenging. To address this, practitioners can build a ‘Franken-Standard’ from existing ASVS/MASVS, adopt a ‘Threat-Model-First’ approach, or contribute to and adapt community efforts for robust security.

🎯 Key Takeaways

The industry currently lacks a dedicated ‘Desktop Application Security Verification Standard’ (DASVS), forcing security teams to improvise with existing web (ASVS) and mobile (MASVS) standards.
Desktop application security is complicated by diverse platforms (Windows, macOS, Linux), language/framework sprawl (C++, C#, Electron), and unique attack surfaces like insecure auto-updaters, DLL hijacking, and inter-process communication (IPC).
Practical strategies include creating a ‘Franken-Standard’ by combining relevant ASVS/MASVS sections with custom desktop controls, employing a ‘Threat-Model-First’ approach (e.g., STRIDE) to generate tailored requirements, or engaging with community projects and adapting existing checklists.

Struggling to find a consistent security standard for desktop apps? I break down why the industry lacks a ‘Desktop ASVS’, and share three practical approaches you can use right now to build your own robust verification framework.

The Gap in Our Armor: The Missing Standard for Desktop App Security (DASVS)

I remember it vividly. We were staring at a new thick-client trading application. The backend team swore it was “just a front-end,” and the desktop devs insisted it was “just a dumb client calling APIs.” Meanwhile, my team was stuck in the middle, trying to figure out how to even begin a security assessment. We spent two days arguing over whether to use the Web Security Verification Standard (ASVS) or the Mobile one (MASVS), knowing neither was a perfect fit. We ended up with a mess of a spreadsheet, cherry-picking controls from both, and I was terrified of what we were missing in the gaps. This is the reality for most of us in the trenches: desktop application security is still the Wild West.

So, Why Are We in This Mess?

It’s not out of malice or incompetence. The industry’s focus shifted, and for good reason. For the last 15+ years, the money, the users, and the attackers have all been focused on web and mobile. As a result, we got fantastic, mature frameworks from organizations like OWASP to help us secure those platforms. Desktop got left behind. The core of the problem is fragmentation:

Diverse Platforms: A security control for a Windows app using the Win32 API is wildly different from one for a macOS app interacting with Keychain, or a Linux app dealing with X11.
Language & Framework Sprawl: How you secure a C++ Qt application is not how you secure a C# .NET app, which is again different from an Electron app that’s essentially a bundled web browser with keys to the kingdom (the OS).
A Different Attack Surface: We’re not just worried about XSS. We’re worried about insecure auto-updaters, DLL hijacking, insecure inter-process communication (IPC), sensitive data written to world-readable temp files, and unsafe deserialization from local configuration files.

Without a common language or checklist like the ASVS, every assessment becomes a bespoke, time-consuming research project. We can do better.

Okay, I’m Stuck. What Can I Do NOW?

Since we can’t just download the “OWASP DASVS” (it doesn’t exist… yet), we have to get creative. Here are three strategies my team uses, ranging from the quick-and-dirty to the architecturally sound.

1. The Quick Fix: Build a “Franken-Standard”

This is the hacky-but-effective approach. You acknowledge that your desktop app is a hybrid beast and build a hybrid checklist. You literally stitch together sections from existing, mature standards. It’s not perfect, but it’s a damn sight better than nothing.

Your checklist might look something like this:

From OWASP ASVS: Steal all the sections related to communication. If your app talks to a backend API, you need V2 (Authentication), V3 (Session Management), V4 (Access Control), V5 (Validation), and V13 (API).
From OWASP MASVS: Borrow heavily from V2 (Data Storage) and V6 (Platform Interaction). This covers things like insecurely storing credentials in a local config file or mishandling filesystem permissions.
The Custom Desktop Section: This is the part you have to build yourself. This is where you add controls specific to the desktop environment.
- Is the installer properly signed?
- Does the auto-updater fetch binaries over HTTPS and verify their signatures?
- Are all binaries compiled with modern memory safety protections (ASLR, DEP)?
- Are there any opportunities for DLL hijacking in the application’s search path?
- Is inter-process communication (IPC) properly secured?

2. The Permanent Fix: The Threat-Model-First Approach

Instead of starting with a generic checklist, start with the application itself. A threat modeling exercise (using a framework like STRIDE) forces you to think like an attacker targeting *your specific application*. You identify assets, trust boundaries, and entry points, and then brainstorm what could go wrong.

For example, you might identify the auto-updater as a critical entry point. Applying STRIDE:

Spoofing: Could an attacker spoof the update server? (Leads to a requirement for TLS and certificate pinning).
Tampering: Could they tamper with the update binary in transit? (Leads to a requirement for code signing and signature verification).
Information Disclosure: Does the update check leak sensitive user or machine info?
Denial of Service: Could a malicious update file crash the application or the entire OS?
Elevation of Privilege: Does the updater run with admin rights? Can a low-privilege user trigger it to overwrite system files? (A classic vulnerability).

Your threat model *generates* the security requirements. Your verification standard is then simply a checklist to ensure those requirements were actually implemented. It’s more work up front, but it produces a tailored, highly effective result.

Pro Tip: Beware the Electron App. Just because an application is built with web technologies (HTML, JS, CSS) doesn’t mean it’s a web app. Electron apps have direct access to the underlying operating system via Node.js APIs. A simple Cross-Site Scripting (XSS) vulnerability can quickly become Remote Code Execution (RCE) if nodeIntegration is enabled. Your “web app” pen test just became an OS-level compromise test.

3. The ‘Community’ Fix: Contribute and Adapt Existing Work

We’re not the only ones with this problem. The Reddit thread that sparked this post proves that. While there’s no single, official standard, there are pockets of excellent work out there we can use as a starting point.

This approach is about actively participating in the solution:

Find and Follow Projects: Keep an eye on the official OWASP Projects list. A Desktop AppSec project has been proposed multiple times. If it gets traction, jump in and contribute.
Adapt Existing Checklists: Look for resources like the “Windows Security Checklist” or “macOS Application Security Guide.” They aren’t holistic standards, but they are great sources for your “Custom Desktop Section” in the Franken-Standard approach.
Focus on CWEs: Familiarize yourself with the Common Weakness Enumerations (CWEs) that are most prevalent in desktop software, like CWE-427 (Uncontrolled Search Path Element) or CWE-788 (Access of Memory Location After End of Buffer).

Choosing Your Path

So which approach is right for you? It depends on your timeline, resources, and the risk profile of the application.

Approach	Speed / Effort	Coverage	Best For…
1. Franken-Standard	Fast / Low Effort	Good, but generic	Quick assessments, teams new to AppSec, compliance-driven checks.
2. Threat Model First	Slow / High Effort	Excellent, highly tailored	High-risk applications, mature security programs, building security in from the start.
3. Community Fix	Ongoing / Variable Effort	Variable, improves over time	Teams wanting to build a long-term, reusable standard and contribute back.

Ultimately, the worst thing you can do is nothing. Don’t let the absence of a perfect, official standard paralyze you. Pick a strategy, start building your process, and iterate. Our adversaries certainly aren’t waiting for a committee to approve a checklist.