Thick Client Security Testing
Security assessment of desktop and thick-client applications — application logic, local storage, authentication, communication, configuration and backend interactions.
Why this assessment matters
Desktop applications run outside the browser, which means their security decisions often live in code an attacker can inspect and modify. Local data stores, configuration files, update mechanisms and client-side trust boundaries create a distinct attack surface that web testing does not cover.
What We Test
Typical coverage for this assessment, tailored to your system during scoping.
- Windows applications
- Desktop applications
- Client-side logic
- Local data storage
- Configuration files
- Authentication
- Authorization
- API communication
- Encryption usage
- Update mechanisms
- Backend interaction
- Sensitive information exposure
How the Assessment Runs
A consistent six-stage process — every stage produces something you can use.
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Discover
Map the application, its components, local data stores, configuration and backend endpoints.
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Assess
Review client-side logic, storage, authentication, communication and update mechanisms.
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Validate
Demonstrate impact on a controlled instance — for example, extracting stored data or bypassing a client-side check.
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Report
Document findings with reproduction steps, evidence and platform-specific remediation.
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Remediate
Guide engineering on server-side enforcement, secure storage and update integrity.
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Retest
Verify fixes against the original findings on the updated build.
Typical Findings
Realistic issue classes commonly discovered during this type of assessment. Your results depend on your system — we do not imply guaranteed findings.
- Sensitive data in unencrypted local storage or configuration files
- Client-side authorization that can be bypassed by modifying the binary
- Weak or missing encryption for local data and communication
- Insecure update mechanisms enabling payload substitution
- Hardcoded credentials or API keys in the application
- Backend endpoints trusting client-supplied identity or state
Deliverables
Everything needed to understand, prioritize and fix what we find.
- Application and component inventory
- Findings with reproduction steps and evidence
- Server-side and client-side remediation guidance
- Retest report for the remediated build
Where Thick Client Security Fits in Your Attack Surface
The shared, data-driven attack-surface map — Thick Client Security is emphasised automatically. Select any node to see its assessment path, related systems and security objective.
Interactive 3D map of the security attack surface — Web, API, Mobile, Thick Client, Cloud, Internal, External, AI and Blockchain. Select a node to explore a service.
- Discover
- Map
- Assess
- Validate
- Correlate
- Risk
- Evidence
- Remediate
- Retest
- Assessment / attack path
- Application / API
- Identity / security core
- Defensive
- Critical risk
Who Needs This
Organizations distributing Windows or desktop applications
Products that process sensitive data outside the browser
Teams whose desktop clients talk to backend APIs
Any application where local trust boundaries are part of the design
Frequently Asked Questions
Do you need the source code?
No. We assess the distributed build, which is what attackers see. Source access can deepen the review when available but is not required.
Which platforms do you cover?
Primarily Windows desktop applications, including .NET and native binaries. Other desktop platforms can be scoped on request.
Is backend testing included?
We test the backend APIs the client communicates with as part of the application’s attack surface. Broader backend work is scoped separately.
Ready to test your application?
Start a scoping conversation about thick client security for your systems.