Broken Authentication & Session Management
Session fixation after login or password reset, JWT tokens accepted with alg: none, refresh tokens that remain valid after logout, password-reset tokens with insufficient entropy, missing step-up authentication on sensitive operations and cookie flags (HttpOnly, Secure, SameSite) that aren't enforced consistently. Most teams harden the login form and stop there; the riskier surface is the full session lifecycle around it.
Why it's missed
Automated scanners test whether a login form exists, not whether the session it creates behaves correctly across logout, password reset, concurrent sessions and privilege changes. We test the complete lifecycle with multiple accounts simultaneously.
Cross-Site Scripting (Stored, Reflected, DOM)
Stored XSS in rich text editors, user profiles and comment fields that render unescaped HTML. Reflected XSS in search parameters, error messages and redirect URLs. DOM-based XSS through postMessage handlers with no origin check, client-side template injection, innerHTML sinks and mutation XSS that bypasses DOMPurify. A working XSS chain can silently exfiltrate session tokens or trigger state-changing actions as the victim.
Why it's missed
Teams assume "we use React" or "we have a CSP" means XSS is solved. We test the actual rendering paths and find the one custom component that bypasses both the framework defaults and the content security policy.
SQL Injection & Server-Side Injection
Classic SQL injection in raw query builders and dynamic sort/filter parameters. NoSQL operator injection ($where, $ne) in MongoDB stores. Server-Side Template Injection (SSTI) in Jinja2, Twig and Thymeleaf. Second-order injection where tainted data is stored safely but later concatenated into a query in a different code path. Command injection through file processing, PDF generation and image manipulation features.
Why it's missed
"We use an ORM" is the most common false sense of security we encounter. We specifically target the raw-query exceptions, dynamic field names and second-order paths where the ORM is bypassed.
Insecure Direct Object References (IDOR)
Endpoints that accept user-controlled IDs (sequential integers, UUIDs, filenames) without verifying that the requesting user owns the referenced object. This manifests on profile pages, data exports, invoice downloads, file attachments and API endpoints that were tested with one account but never verified with a second account at a different privilege level. IDOR is the most common high-severity finding in our web application security testing engagements.
Why it's missed
Scanners cannot reason about object ownership. Finding IDOR requires testing every sensitive endpoint with two real accounts of different privilege levels side by side, which is exactly how our testers work.
Business Logic Flaws
Price manipulation by intercepting and modifying request parameters. Coupon stacking and discount abuse. Race conditions on inventory, balance or vote endpoints. Workflow step skipping where a user jumps directly from step 1 to step 5 without completing validation steps. Privilege escalation through state manipulation, such as changing a role parameter or replaying an admin invite token. These flaws exist because the application's intended behavior was never formally defined as a security boundary.
Why it's missed
No scanner can understand what a "valid" checkout flow looks like in your application. Our testers read the product documentation, map the workflows and then systematically try to break the assumptions each workflow depends on.
Cross-Site Request Forgery & Clickjacking
State-changing actions (account settings, email change, password reset, fund transfers) that lack CSRF tokens or rely solely on cookies for authentication. Clickjacking through missing X-Frame-Options and frame-ancestors CSP directives, allowing an attacker to overlay invisible iframes on a trusted page and trick users into performing unintended actions. Login CSRF where an attacker forces a victim to authenticate to an attacker-controlled account.
Why it's missed
SPA frameworks often handle CSRF tokens inconsistently across routes, especially on endpoints added after the initial build. We test every state-changing endpoint individually, not just the ones the framework auto-protects.
Frequently Asked Questions About Web Application Security Testing
What does web application security testing cover beyond automated scanning?
Web application security testing goes beyond automated scanning to include manual testing of authentication flows, session management, business logic flaws, access control enforcement, input validation and output encoding. Testers simulate real attacker behavior by chaining low-severity issues into high-impact exploit paths, testing role-based access with multiple user accounts side by side, and validating that security controls work under edge-case conditions that scanners cannot replicate.
How is web application security testing different from a vulnerability scan?
A vulnerability scan runs automated tools against known signatures and misconfigurations. Web application security testing includes that scanning layer but adds manual penetration testing: a tester logs in with real credentials, walks through business workflows, tests access control between roles, probes input handling with context-aware payloads, and verifies whether each finding is actually exploitable in your specific environment. The result is a report with zero false positives and real business-impact analysis, not a 200-page scanner dump.
Which standards does your web application security testing follow?
Our web application security testing is aligned to the OWASP Top 10, OWASP Application Security Verification Standard (ASVS) Level 2, CWE/SANS Top 25 and CVSS 4.0 for vulnerability scoring. Reports include PCI DSS mapping where applicable. Every finding is traceable to an industry-recognized classification, which is what auditors, compliance teams and enterprise customers expect.
How long does a web application security test take?
A typical web application security test takes one to three weeks depending on the size and complexity of the application. A small single-purpose app with 30 to 50 endpoints can complete in one week. A large SaaS platform with multiple user roles, API integrations and complex business logic typically requires two to three weeks. We confirm the timeline during scoping before any testing begins, so there are no surprises.
Do you provide a retest after we fix the vulnerabilities?
Yes. Every web application security testing engagement includes one full retest cycle at no additional cost. Once your team has remediated the reported findings, we re-verify each issue individually and issue a signed closure report confirming which vulnerabilities were fixed. This closure report is the document most auditors, enterprise customers and compliance frameworks require as evidence of remediation.