SaaS Security Audit for Products That Hold Other People's Data

An independent, hands-on review of your application, tenant isolation, authentication, cloud configuration, and secrets — the parts of a SaaS that actually get breached. Every finding reproduced with proof and paired with a fix you can ship.

The breach is almost never the front door

SaaS breaches rarely come from a kicked-in perimeter. They come from an authorization check that runs in the browser but not on the server, a tenant ID a user can change in a URL, an S3 bucket left public, an API key committed to a repository, or a password reset flow that leaks whether an account exists. These are the failures a multi-tenant product is uniquely exposed to, and they are exactly the failures a generic vulnerability scan walks right past.

A SaaS security audit is a structured, manual hunt for those failures. We log in as a tenant and try to reach another tenant's data. We tamper with every identifier the client sends. We map the auth and permission model and probe it from below. We read the cloud configuration and the secrets handling. The output is a report that tells you what an attacker would actually find — with proof — and a remediation plan that closes it.

What the audit covers

Multi-tenant data isolation — can one tenant read, write, or enumerate another tenant's records
Authentication — session handling, password reset, MFA, OAuth/SSO flows, and account enumeration
Authorization — broken object-level and function-level access control (IDOR, privilege escalation)
Application layer — injection, XSS, SSRF, request tampering, and the OWASP Top 10
API security — auth, rate limiting, mass assignment, and the OWASP API Top 10
Cloud configuration — IAM, storage buckets, security groups, public exposure, and logging gaps
Secrets management — keys in source, env handling, rotation, and over-scoped credentials
Business logic — abuse of trials, billing, invitations, and tenant provisioning flows
Dependency and supply-chain review — known-vulnerable packages and risky transitive deps
SOC 2 readiness mapping — findings tied to the Common Criteria auditors evaluate

Our methodology

The audit starts with a scoping call and a quick architecture walkthrough so we understand the tenancy model, the trust boundaries, and what matters most to you. We provision test tenants we control, then work through a structured methodology that blends OWASP testing guides with the SaaS-specific checks that scanners miss. Findings are reproduced by hand, rated with CVSS, and written up so an engineer can fix them and an auditor can read them.

Scoping → testing window (1 to 3 weeks typical) → report and debrief call → complimentary retest of fixed findings. You get a developer-grade report, an executive summary, and a remediation plan prioritized by real-world risk.

Tools & standards

OWASP Top 10 + ASVS

OWASP API Top 10

Burp Suite Pro

CVSS v3.1 scoring

MITRE ATT&CK mapping

Cloud config review (AWS/GCP)

Secrets scanning

Manual logic testing

SOC 2 CC mapping

The same testing discipline runs through every web app pentest, penetration test, and managed security engagement we run.

Why an independent audit matters

The team that built the system shares its blind spots. An independent audit brings an attacker's eyes to assumptions the builders never questioned — the permission that was "obviously" safe, the tenant check that "always" runs, the bucket that was "only" for assets. That outside perspective is exactly what a SOC 2 auditor and an enterprise security reviewer want to see, and it is what turns a stalled deal into a signed one.

Because QUANT LAB USA also builds software, the report is not a wall of jargon you have to translate. Findings come with code-level guidance, and if you want the fixes implemented, we can do that too.

SaaS security audits served from Macon, GA, with clients across Atlanta, New York, San Francisco, and the rest of the US.

Pricing

Fixed-fee per engagement, scoped to the size and complexity of the product. Typical ranges:

Focused audit — single app, core tenant-isolation and auth review: $7k – $15k
Standard SaaS audit — app, API, authz, and cloud configuration: $14k – $28k
Comprehensive audit — full app, API, cloud, secrets, and logic testing: $25k – $45k
SOC 2 readiness audit mapped to the Common Criteria: $18k – $40k
Scoping and architecture review session: $1,500 flat

Every engagement includes a complimentary retest of fixed findings. Recurring annual audits and an ongoing retainer are available.

What you get

A developer-grade report — every finding with proof-of-concept, CVSS severity, and reproduction steps
An executive summary suitable for the board, auditors, and enterprise prospects
A remediation plan prioritized by real-world risk with code-level guidance
SOC 2 Common Criteria mapping for the findings that touch your control set
A live debrief call to walk your engineers through every issue
A complimentary retest of fixed findings to confirm closure
An attestation letter you can share with customers once findings are remediated

FAQs

What is the difference between a SaaS security audit and a generic pentest?

A SaaS audit goes beyond the perimeter. It tests the things unique to multi-tenant software — whether one tenant can reach another tenant's data, whether role and permission checks hold on the server, how secrets and keys are managed, and whether the cloud configuration leaks anything. A generic pentest checks the front door; a SaaS audit checks every door between customers.

Will this help us pass a SOC 2 audit or a customer security questionnaire?

Yes. Findings map to SOC 2 Common Criteria and to the questions enterprise buyers ask in security questionnaires. You get a clean report you can share with auditors and prospects, and a remediation list that closes the gaps before they become blockers in a deal.

Do you test against production or a staging environment?

Usually a staging or pre-production environment that mirrors production, seeded with test tenants we control. Where production testing is required, we coordinate a window, rate-limit our activity, and avoid destructive checks. We never touch real customer data.

How do you make sure the findings are real and not just scanner noise?

Every finding is reproduced by hand with a proof-of-concept, a severity rating using CVSS, and the exact steps to trigger it. Automated scanning is a starting point, not the report. If we cannot demonstrate it, it does not go in as a vulnerability.

Do you help fix the issues or just report them?

Both. The report includes a prioritized remediation plan with concrete code-level guidance, and we offer a complimentary retest of fixed findings. Because we are also a software development firm, we can implement the fixes directly if you want us to.

Security & compliance reading

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Related services

Web App Penetration Testing

Deep manual testing of a single web application.

Managed Security Services

Ongoing monitoring and recurring testing on retainer.

Code Audit Services

Source-level review of security and code quality.

Background reading on what to expect: the founder's pentest buyer guide and how to prepare for a SOC 2 audit. To scope an audit, contact us directly.

SaaS Security Audit — Where We Serve

Georgia-based security team, working with SaaS companies across 14 US metros. Audits run remotely; in-person debriefs available in Atlanta and the Southeast.