See all servicesWeb Application Security
Vlad Sedenko · Web Product DeveloperService / Independent specialist
Find and fix security risks before they become incidents
A product can look finished while weak access control, exposed keys or an unsafe form quietly puts customer data and the business at risk. I review the application as a senior developer, explain the findings in business terms and fix the issues in the code instead of stopping at a report.
- Authentication, roles and permissions checked against real user flows
- Exposed secrets, unsafe inputs and vulnerable dependencies identified
- Production configuration, cookies, headers and admin routes reviewed
- Prioritized remediation with verification after the fixes
/ Fit
Who this is for
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Founders preparing a website, SaaS product or AI-built prototype for launch
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Teams handling accounts, payments, personal data or internal business information
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Companies that inherited a codebase and do not know its current security posture
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Products that need practical remediation rather than a report nobody implements
/ The review
What the security review covers
Authentication and sessions
Login, password reset, session expiry, cookies and account recovery.
Authorization and access control
Roles, tenant isolation, admin routes and protection against users accessing another user's data.
Input and data handling
Validation, file uploads, forms and common injection or cross-site scripting risks.
Secrets and configuration
API keys, environment variables, debug settings, CORS, security headers and production exposure.
Dependencies and integrations
Vulnerable packages, webhook verification, third-party APIs and payment-related flows.
Operational safeguards
Rate limiting, logging, error handling, backups and a clear list of residual risks.
/ Deliverables
What you receive
A prioritized report with severity, business impact and reproducible evidence; a remediation plan ordered by risk and effort; hands-on fixes for the agreed scope; and a verification pass showing what was resolved and what still requires attention.
/ Process
How it works
Scope
We identify the application, sensitive flows, environments and access needed for the review.
Review
I inspect the code, configuration and critical user journeys using manual checks and appropriate tooling.
Prioritize
Findings are ranked by realistic risk, business impact and remediation effort.
Fix and verify
I implement the agreed changes and re-test the affected flows before handover.
10+
years in web development
120+
launched projects
24h
reply, EU-based
Request a security review
Send me the product URL, stack and the flows that handle accounts, payments or sensitive data. I will reply within 24 hours with the right scope and next step.
Frequently asked questions
Who is Web Application Security for?
Web Application Security is for founders, small businesses and teams that need hands-on work on a website or web product, not just high-level recommendations.
How does the engagement start?
We start with a short description of your goal, current state and constraints. I then suggest the scope, priorities, next steps and a realistic delivery model.
Do you implement recommendations in code?
Yes. I work as a developer, so I can not only prepare a plan but also implement changes in code, site structure, integrations and configuration.
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