Web Application Security

Find what attackers
find in your
web applications

Manual, expert-led penetration testing that goes beyond automated scanning — uncovering business logic flaws, authentication bypasses, and chained vulnerabilities that tools miss entirely.

100%
OWASP Top 10 coverage
48h
First critical finding alert
200+
App assessments delivered
https://app.targetclient.com
Testing
Findings 14 total · 3 critical
Critical SQL injection — auth bypass /api/login
Critical IDOR — access any user account /api/users/{id}
High Stored XSS — admin panel /admin/comments
High JWT algorithm confusion /api/v2/token
Medium CSRF — no SameSite cookie /account/settings
OWASP Top 10 coverage
Broken Access Control
Done
Cryptographic Failures
Done
Injection
Done
Insecure Design
Active
Security Misconfiguration
Next
Overview

More than a scanner. A real adversary's perspective.

Automated vulnerability scanners catch a fraction of what a skilled attacker would find. They can't reason about business logic, chain vulnerabilities, or understand context. Our web application penetration tests are conducted by experienced offensive security engineers who approach your application the way an attacker would — creatively, persistently, and without limits.

Every engagement is scoped to your application's specific risk profile. We test your web apps and APIs against the full OWASP Top 10 and beyond — including authentication and session management flaws, insecure direct object references, injection vulnerabilities, business logic abuse, and server-side request forgery, among others.

At the end of every engagement, you receive a report written for both your engineering team and your leadership — with clear technical reproduction steps, business impact context, and a prioritized remediation roadmap.

3x
More findings than automated scanning alone
48h
Time to first critical finding notification
100%
Remediation retest included in every engagement
Every engagement includes
Full-scope application
security testing
Authenticated & unauthenticated testing
We test all privilege levels — anonymous user, standard user, admin, and API access
Full API coverage
REST, GraphQL, and WebSocket endpoints tested alongside the web front-end
Business logic testing
Workflow abuse, price manipulation, privilege escalation paths unique to your application
Third-party integration review
OAuth flows, SSO configurations, payment integrations, and webhook security
Dual-audience report
Technical report for developers + executive summary for leadership and board
Free remediation retest
We verify every fix at no additional cost — ensuring issues are truly resolved
Letter of attestation
Compliance-ready letter confirming scope, methodology, and testing completion
Coverage

OWASP Top 10 and beyond

The OWASP Top 10 is the baseline — not the ceiling. Our testing covers the full list plus application-specific vulnerabilities that only expert manual testing can surface.

A01
Broken Access Control
IDOR, privilege escalation, path traversal, missing function-level access controls, and horizontal vs vertical authorization failures.
A02
Cryptographic Failures
Weak ciphers, improper TLS configuration, insecure data storage, hardcoded credentials, and secrets in source or responses.
A03
Injection
SQL, NoSQL, LDAP, command, and template injection. We test every input surface — including headers, cookies, and JSON bodies.
A04
Insecure Design
Business logic flaws, missing rate limits, workflow bypass, and architectural weaknesses that scanners can't reason about.
A05
Security Misconfiguration
Exposed admin interfaces, verbose errors, default credentials, unnecessary features enabled, and misconfigured cloud storage.
A06
Vulnerable Components
Known CVEs in frameworks, libraries, and third-party components — cross-referenced against your specific application version.
A07
Auth & Session Failures
Weak password policies, insecure session tokens, JWT vulnerabilities, broken MFA, and credential stuffing susceptibility.
A08
Software & Data Integrity Failures
Insecure deserialization, CI/CD pipeline weaknesses, unsigned updates, and unverified third-party plugin integrity.
A09
Logging & Monitoring Failures
Assessment of what gets logged, what doesn't, how alerts are triggered, and whether active attacks would be detected in time.
A10
Server-Side Request Forgery
SSRF via URL parameters, webhooks, PDF generators, file imports, and other server-initiated request vectors — including blind SSRF.
Methodology

How we approach every engagement

We follow a structured five-phase methodology built on industry standards — OWASP Testing Guide, PTES, and WSTG — customized for your application's specific architecture, technology stack, and business context.

Scoping & Reconnaissance
We map the full application surface — endpoints, tech stack, authentication mechanisms, and third-party integrations — before touching a single input.
Automated Discovery
Targeted automated scanning to build a baseline — crawling, fingerprinting, and low-hanging fruit identification — setting the stage for manual expert testing.
Manual Expert Testing
The core of every engagement. Our engineers manually probe business logic, chain vulnerabilities, test authentication flows, and attempt real exploitation — not just identification.
Reporting
Every finding documented with CVSS score, proof-of-concept reproduction steps, business impact assessment, and specific remediation guidance — not generic advice.
Retest & Attestation
Once your team remediates findings, we retest every fix and issue an updated report — plus a letter of attestation confirming security posture for compliance or partners.
Engagement Types

Tailored to your situation

No two applications are the same. We scope each engagement to match your technology, your risk appetite, and your timeline.

Black Box
Zero-knowledge testing
We start with no credentials or documentation — exactly like an external attacker. Best for validating your external perimeter and public-facing security posture before a product launch or audit.
External attacker simulationPre-launchCompliance
Grey Box
Partial-knowledge testing
We're provided user-level credentials and limited documentation. The most efficient approach for most engagements — simulates a compromised account or a malicious insider and maximizes depth of coverage.
Insider threatMost commonBest ROI
White Box
Full-knowledge testing
Full access to source code, architecture docs, and admin credentials. The deepest possible assessment — ideal for pre-release security reviews, major architectural changes, or applications handling highly sensitive data.
Source code reviewPre-releaseMaximum depth
API-Focused
API penetration test
Dedicated testing of REST, GraphQL, and WebSocket APIs — especially valuable for mobile backends, microservices, and developer-facing APIs. Includes authentication, rate limiting, and business logic abuse.
REST & GraphQLMobile backendsMicroservices
Continuous
Ongoing web app testing
Always-on testing that covers new features and releases as they ship. Ideal for SaaS companies and fast-moving engineering teams who can't afford gaps between point-in-time tests.
SaaSAgile teamsMonthly retainer
Pre-Compliance
Compliance-scoped assessment
Scoped specifically to satisfy PCI-DSS, SOC 2, HIPAA, or ISO 27001 requirements. Includes the report format, letter of attestation, and evidence package your auditors need.
PCI-DSSSOC 2ISO 27001
Compliance

Satisfy your audit requirements

Web application penetration testing is explicitly required or strongly recommended by most major compliance frameworks. Our reports are formatted to satisfy auditor requirements, with evidence packages tailored to each standard.

PCI-DSS v4
Requirement 11.3 mandates annual web app pentests for card data environments
SOC 2 Type II
Pentest evidence supports availability and security trust service criteria
ISO 27001
Annex A.14.2 requires security testing throughout development lifecycle
HIPAA
Technical safeguard evaluation includes application-level vulnerability assessment
NIST CSF
Identify function requires thorough assessment of application vulnerabilities
Cyber Insurance
Most carriers now require or incentivize annual web application penetration testing
Report deliverables
Full technical findings report with CVSS scores and PoC steps
Executive summary for leadership and board presentation
Prioritized remediation roadmap with severity-based ordering
Letter of attestation confirming scope, dates, and methodology
Retest report confirming remediation of all findings
OWASP Top 10 coverage matrix for auditor reference
PCI-DSS / SOC 2 evidence package on request
Standards alignment
OWASP WSTGPTESOWASP Top 10OWASP API Top 10CWE/SANS Top 25CVSS v3.1NIST SP 800-115
Client Results

What our clients say

"

Radical found a critical IDOR vulnerability in our API that our internal team and a previous vendor had missed entirely. The report was the clearest we'd ever received — our developers actually read it.

MN
CTO, Micro Notes
B2B SaaS Platform
"

We needed a web app pentest to satisfy our SOC 2 audit. Radical delivered exactly what our auditors needed — thorough, well-documented, and the remediation support was genuinely helpful.

WH
CTO, Wheel Health
Healthcare Technology
"

We run a complex consumer web app with a lot of user-generated content. Radical's team found chained XSS vulnerabilities that automated tools had no chance of surfacing. Worth every dollar.

LA
CPO, Luminary Audio
Consumer Platform
Why Radical Security

The Radical difference

We don't apply checklists. Every web application engagement is built around understanding your specific architecture, your business logic, and the adversaries most likely to target you.

Manual-first
Automated tools find 30% of what we find. The other 70% — business logic flaws, chained vulnerabilities, auth bypasses — only manual expertise can surface.
Senior practitioners
Every engagement is run by experienced application security engineers. No junior staff learning on your application — seasoned experts from day one.
Actionable reports
Reports written for developers — not just to satisfy auditors. Every finding includes specific code-level remediation guidance your team can act on immediately.
We stay until it's fixed
Remediation retesting is included. We don't deliver a report and disappear — we stay engaged until every finding is confirmed resolved.

Ready to test your web application?

Tell us about your application and we'll scope an engagement matched to your tech stack, your compliance requirements, and your timeline.

Request a Scoping Call
No commitment required. Scoping is always free.
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