Scanner, pentest or bug bounty? What each one finds, what each one costs, and when to combine them
The three approaches don't compete — they cover different risks. A straight guide to deciding where to put your offensive security budget, with what each actually delivers and the mistakes of teams that pick only one.
The wrong question
"We already run a scanner, do we need a pentest?" or "Doesn’t a bug bounty replace pentesting?" are questions we hear every week. The honest answer: they are tools for different risks, and a mature company uses all three — in proportions that depend on its stage. The mistake is assuming one covers another.
What each approach actually finds
Scanner (DAST/SAST/SCA)
Automates the search for known patterns: vulnerable versions, missing headers, obvious injections, insecure configuration. Runs every night, costs little per run, is indispensable hygiene.
What it doesn’t do: understand business logic, chain flaws, test authorization between users, evaluate an AI agent. It produces false positives that eat hours of your team and false negatives that give a false sense of security. In our pentests, most critical findings fall in categories a scanner cannot detect by construction: BOLA, logic abuse, race conditions, prompt injection.
Manual pentest
An expert, with a defined scope and time box, tries to compromise the target the way an attacker would — while documenting every step. Finds what requires creativity and context: "the coupon applies twice if the requests are concurrent", "the customer UUID leaks in the webhook and opens anyone’s invoice".
Delivers evidence (reproducible PoC), business risk rating, remediation plan and retest. It is the format audits (PCI DSS, ISO 27001, SOC 2) and enterprise customers require. Limitation: it is a snapshot — it covers that scope in that period.
Bug bounty
Hundreds of independent researchers, paid per result, testing continuously. Excellent for a large public surface and for finding what nobody thought of. Finds things pentests don’t, through volume and diversity of perspectives.
Limitations that are usually underestimated: no coverage guarantee (nobody is obliged to test the boring flow), it does not serve as audit evidence, it needs an internal team for triage (the volume of duplicate and invalid reports is large), and it exposes the application to uncoordinated testing — a problem in regulated environments or with sensitive data. And the cost is unpredictable: one critical can cost more than an entire pentest.
Side by side
| Criterion | Scanner | Pentest | Bug bounty |
|---|---|---|---|
| Business logic and authorization | No | Yes | Partial |
| Guaranteed scope coverage | Yes (shallow) | Yes | No |
| Audit / customer evidence | No | Yes | No |
| AI systems / agents | No | Yes | Rare |
| Continuity | Daily | Point in time | Continuous |
| Cost | Low, fixed | Medium, fixed | Variable |
| Internal effort | False-positive triage | Low | High (triage) |
| Regulated environments | OK | OK | Careful |
When to use each
- Every company with exposed software: scanner in CI/CD from day one. Not optional.
- Before a launch, an audit, an enterprise contract, or after a major change: pentest. It is the only one of the three that produces the document those situations require.
- Mature application, with a security team for triage, a large public surface and no strong regulatory constraint: bug bounty as a continuous layer — after a pentest has removed the obvious, otherwise you pay bounties for what a pentest would find at a fixed price.
The most common mistakes
- Scanner output with a consultancy logo sold as a pentest. If the report has no manual PoC and no chaining, it’s a scan. Ask how many hours of manual testing are in scope.
- Bug bounty before pentest. Result: paying for dozens of simple findings and dealing with researchers frustrated by duplicates.
- Annual pentest as the only control. Twelve months is too long between snapshots; combine with continuous scanning and pentests per significant change.
- Ignoring AI. None of the three covers chatbots and agents by default; AI/LLM pentesting is explicit scope.
A practical model by stage
- Startup / new product: scanner in CI + pentest before go-live and before the first large customer.
- Regulated scale-up (fintech, health): scanner + semi-annual or per-critical-release pentest + AI pentest once there is an assistant in production. Private bug bounty only with a triage team.
- Enterprise: scanner + pentest program by criticality (quarterly on core systems) + public bug bounty as an additional layer.
How Pentest Machine tests this
We do the part scanners and bounties don’t: manual testing by senior experts, accelerated by AI and in-house tooling to cover more surface in the same time, with an executive + technical report, a PoC for every finding and the retest included. If you already have a scanner and are evaluating a bounty, a pentest first is what makes the bounty cheap.