Product Security Testing

SaaS VAPT, web app, and API penetration testing

Careful, scoped testing of SaaS applications, customer portals, admin panels, mobile apps, and REST/GraphQL APIs. We align on timing, scope, and non-disruptive methods so your team can review findings with confidence.

Third-party testing with fixed scope, agreed windows, and controlled methods.

Practice record

700+ security engagements

Manual testing across SaaS products, customer portals, APIs, and buyer-facing release cycles.

Training target

DVNA: 756+ GitHub stars

A public vulnerable application maintained for practitioners learning how real app attack paths behave.

Buyer proof

Sample report available

Engineering teams can inspect reproduction steps, exploit paths, remediation notes, and retest framing before kickoff.

Input Validation & Injection

We start by modeling how attackers probe inputs, then trace how that data moves through parsers, resolvers, and serializers. Appsecco testing validates each boundary with scoped payloads to see where assumptions break without disrupting production traffic.

Example Finding

A search filter accepted raw operators in a GraphQL query, allowing limited record inference beyond the intended query shape. We mapped the exact parsing path and recommended parameterized filters with allowlisted fields.

Authentication & Authorization

We model how attackers move from login to tokens, sessions, and privilege boundaries. Appsecco testing traces each decision point - issuance, storage, refresh, and access checks - to confirm your auth flows enforce identity and tenant isolation as designed.

Example Finding

Refresh tokens were accepted without validating the intended audience, allowing a valid token from one app to access data in another. We documented the exact flow and recommended scoped token audiences with enforced checks.

Business Logic Abuse

We model how a real attacker stitches together legitimate features - reordering steps, skipping gates, and chaining flows that were never designed to connect. Appsecco testing walks each decision path to confirm your product rules hold under out-of-order and edge-case sequences.

Example Finding

An upgrade workflow accepted a step-complete flag before payment confirmation, enabling feature access without charge. We mapped the exact sequence and recommended server-side state validation at each transition.

API Abuse & Protocol Confusion

Attackers look for gaps between API intent and protocol reality - switching verbs, replaying requests, and nudging headers to see what the service actually enforces. Appsecco testing recreates those behaviors with scoped, non-disruptive probes, then traces how your API parses and authorizes each variation.

Example Finding

A sensitive action accepted GET requests alongside POST, which bypassed CSRF protections in a specific route. We documented the parsing path and recommended strict method enforcement with consistent handler validation.

Client-side & JavaScript Risks

Attackers probe the browser runtime because it reveals how data is rendered, stored, and reused. Appsecco testing traces user-controlled input through DOM sinks, template bindings, and storage APIs, then validates CSP, CORS, and content-type handling to confirm the client stays within intended boundaries.

Example Finding

A support note renderer accepted HTML in a preview pane, which flowed into an admin dashboard view and executed as script. We mapped the rendering path and recommended strict sanitization with an allowlist plus CSP hardening.

Enumeration, Rate Limits & Resilience

Attackers map endpoints and automation boundaries before they try to escalate; that behavior is why Appsecco testing pairs route discovery with control validation. We assess hidden routes, GraphQL introspection, and predictable identifiers, then verify rate limits, lockouts, and retry controls so automated probing stays contained.

Example Finding

A password reset endpoint returned different responses for valid and invalid users and lacked per-tenant throttling. We documented the sequence and recommended uniform responses with rate limits keyed by account and IP.

Why teams trust app testing here

Application testing authority is easiest to judge from the artifacts

Strong appsec practices show their work through training targets, clear reporting, and case studies that go beyond checklist language.

AM

Practice lead

Akash Mahajan

Founder & CEO

Akash leads Appsecco's product security testing practice and the public research work around it. Buyers usually inspect the methods, labs, and reporting artifacts before they commission an engagement. This section makes that trail easier to follow.

  • 10+ years in product security and 700+ security engagements
  • Conference speaker at BlackHat, OWASP, and regional security events
  • Author of open-source security training, MCP testing resources, and practitioner checklists
LinkedIn GitHub Appsecco Open Source

Public artifacts and method signals

The public materials here are less about slogans and more about whether the practice can teach, document, and explain the same attack paths it tests in client systems.

DVNA

756+ GitHub stars

A deliberately vulnerable Node.js application used by practitioners to learn how real application flaws behave under manual testing.

Sample report

Public report artifact

Shows how reproduction steps, exploit paths, and remediation guidance are written for engineering review.

Methodology

Testing model

The published approach for moving from attacker behavior to evidence, prioritization, and fix verification.

Application proof paths

These routes show what the practice looks like in real product environments, especially around business logic, authorization, and tenant boundaries.

B2B SaaS case study

Business logic and auth

A closer look at how manual testing surfaced chained authorization and workflow issues beyond automation.

E-commerce SaaS case study

Tenant isolation and APIs

Cross-tenant data exposure, GraphQL surface, and access control evidence from a multi-tenant platform review.

Reports & deliverables

Review package

What product teams receive when they need findings that engineering, security, and buyers can all use.

What recent buyers say after the review

"The kind of vulnerabilities they found were things we never expected - things which were not on our radar. That changed how we think about our own attack surface."

Founder & CEO

Asia's leading Threat Intel Company

"Found multiple interesting exploitable vulnerabilities across our product. Clear reporting, thorough walkthroughs of each finding, and they stayed engaged until every issue was resolved."

Manager

Most popular Vulnerability Scanner (100+ countries)

"We engaged with Appsecco for red teaming. Their findings were specific, well-documented, and gave our team a clear path to remediation."

Senior Expert

European Giant in FinTech

Reference-ready next step

Need the closest application-testing proof path?

We can start from the exact buyer material your team is likely to inspect first: a report sample, a SaaS case study, or the app-testing methodology.

The point is not to show everything at once. It is to make it easy for a buyer to inspect the exact kind of artifact they would use internally.

Request scoped review

Apps & APIs FAQ

What exactly is in scope for Apps & APIs testing?

We align on specific apps, environments, and endpoints before testing starts. Scope includes SaaS web apps, customer portals, admin panels, mobile front-ends, and the APIs they call, with routes, roles, and data types documented so your team can review coverage clearly.

How do you show evidence for each finding?

Each issue includes a reproducible path, affected endpoints or screens, and the exact condition that failed. We keep steps concise so engineering, security, and audit reviewers can validate the risk and the fix.

What do we receive at the end of the engagement?

You receive a VAPT-style report tailored for product teams: findings with remediation guidance, severity rationale, scope notes, and an executive summary. We also provide a walkthrough to confirm interpretation and answer questions.

Do you provide a VAPT certificate?

We provide a detailed VAPT or penetration testing report, scope statement, retest notes when applicable, and attestation-style documentation on request for customer security reviews, audits, or procurement. We do not issue a generic certificate that implies systems are permanently secure; the documentation states what was tested, when, and what evidence was observed.

Can you test production systems safely?

When production testing is required, we coordinate windows, rate limits, and non-disruptive techniques with your team. If a staging environment is preferred, we mirror the same scope and confirm any production-only behaviors separately.

Do you retest fixes or help validate remediation?

Yes. We can retest confirmed fixes and document closure with the same evidence-driven format, so internal reviews have a clear before-and-after record.

Explore application attack paths

Related app and API security services and resources

Continue from app security concepts into API testing scope, business logic abuse, pentest planning, and application attack research.

Glossary

API Security Testing

Testing methodology for API authorization, data exposure, injection, rate limits, and OWASP API risks.

Glossary

Business Logic Testing

Manual testing for workflow abuse, authorization gaps, pricing flaws, privilege misuse, and edge-case exploitation.

Glossary

Penetration Testing

How structured security testing identifies exploitable weaknesses across application, API, and infrastructure surfaces.

Guide

First Pentest Guide

A practical guide for preparing scope, access, timelines, and expectations before a first product security test.

Guide

Pentest RFP Template

A buyer-focused template for defining product security testing scope, expectations, and vendor comparison criteria.

Blog

Hacking Apps Using NoSQL Injection

A walkthrough of how NoSQL injection changes query behavior and exposes application data.

Blog

Server Side Request Forgery via HTML Injection in PDF Download

A real-world application testing story chaining PDF HTML injection into SSRF against AWS infrastructure.

Blog

Microservices Authorization Using Open Policy Agent and Traefik

Authorization patterns for API gateway enforcement in microservice architectures.

Blog

Exploiting weak configurations in Amazon Cognito in AWS

How to detect and exploit misconfigured Amazon Cognito identity pools, covering federated identity abuse and techniques found during real web and mobile application assessments.

Safe next step

Review the scope together.No obligation to proceed.

We can walk through your apps and APIs, confirm testing windows, and share a fixed quote if useful.

Discuss your scope

or view a sample report first

No sales pressure
Fixed scope and pricing
You choose the pace