When someone asks "do we need a security audit," the honest answer is: which kind? The types of security audits an organization might run cover very different ground — a SOC 2 compliance audit checks controls against a framework, a penetration test tries to actually break in, a code audit reads your source line by line, and an architecture review looks at how systems are designed to fail. Conflating them is how companies end up with a clean compliance report and a breach three months later.
This post walks through the main categories, what each one actually produces, and when you'd reach for it.
What Is a Compliance Audit, and What Does It Actually Check?
Compliance audits — SOC 2, ISO 27001, PCI DSS, HIPAA — verify that an organization has implemented and is operating a defined set of controls. An auditor collects evidence (access logs, policy documents, change tickets, screenshots of configurations) and tests whether controls operated consistently over an audit period, typically three to twelve months for SOC 2 Type II.
These audits are valuable for building trust with customers and partners, and they force organizations to formalize policies that might otherwise live only in someone's head. But a compliance audit is not the same as a security assessment — it's entirely possible to pass a SOC 2 audit while having exploitable vulnerabilities in production, because the audit tests process adherence, not attack resistance.
What Does a Penetration Test Actually Cover?
Penetration testing is adversarial by design. A tester (internal or third-party) actively tries to exploit weaknesses in an application, network, or organization, often within a defined scope and time window. Results are typically categorized by severity and include proof-of-concept exploitation steps, not just theoretical findings.
Pen tests are point-in-time snapshots. A clean pen test report from six months ago tells you very little about your current exposure, especially if the codebase has shipped hundreds of changes since. This is one reason continuous scanning tools have grown alongside, not instead of, periodic pen testing — the two serve different cadences.
What Is a Code Audit, and How Is It Different From SAST?
A code audit is a manual (or manual-plus-tooling) review of source code for security defects — injection flaws, broken authentication, insecure deserialization, logic errors that automated tools miss. Static analysis (SAST) tools can flag pattern-based issues automatically, but a human code audit typically goes deeper into business logic flaws that don't match any known pattern.
Code audits are expensive relative to automated scanning, so they're usually reserved for high-risk components — authentication systems, payment processing, cryptographic implementations — rather than an entire codebase.
What Is an Architecture or Design Review?
Architecture reviews look at how systems are designed before or after they're built: trust boundaries, data flow, failure modes, blast radius if one component is compromised. This is closely related to threat modeling, and it's the audit type most likely to catch systemic issues — like a single compromised service having access to every downstream system — that code-level scanning can't see because the flaw isn't in any one file.
This is also where security by default as a design principle gets tested. An architecture review asks whether insecure configurations are even possible by default, not just whether a specific instance was misconfigured.
How Do These Audit Types Work Together?
None of these audit types substitutes for the others. A mature security program layers them: continuous automated scanning (SCA, SAST, DAST) catches known issues on every commit, periodic penetration tests validate that defenses hold against a motivated human attacker, targeted code audits cover the highest-risk components, architecture reviews happen at design time and after major changes, and compliance audits provide the external attestation customers and regulators expect.
Trying to satisfy all of these with a single audit type is a common mistake — treating a SOC 2 report as proof of technical security, or treating a pen test as compliance evidence, both create gaps that surface at the worst time. Tools that combine SAST, SCA, and DAST into one pipeline (see our SAST/DAST product page) help close the continuous-scanning gap, but they don't replace the audit types that require a human judgment call.
FAQ
How often should a company get a penetration test?
Annually at minimum, and after any major architecture change, is a common baseline. Regulated industries and larger attack surfaces often justify semi-annual or quarterly testing.
Is a vulnerability scan the same as a security audit?
No. A vulnerability scan is an automated, largely unauthenticated check for known issues. It's a useful input to an audit but isn't a substitute for the broader review process an audit implies.
What is "security by default" in the context of an audit?
It refers to systems being configured safely out of the box — for example, encryption enabled by default rather than requiring an administrator to turn it on. Auditors increasingly check for this because opt-in security controls are frequently never opted into.
Do small companies need all these audit types?
Not all at once. Most early-stage companies start with automated scanning and a lightweight architecture review, adding formal compliance audits and penetration testing as customer contracts or regulatory requirements demand them.