A Series A round changes who is watching your security. Customers start sending questionnaires, investors ask about risk, and engineers ship faster than any review process can follow. This guide sets out a practical security program for startup CEOs, CTOs and CSOs who need protection in place without a large team. It covers the controls to start with, secure code practices, the SOC 2 path and an incident plan you can write this month.
Why Series A is the right time to build a program
Security is cheapest before it becomes urgent. At Series A you have paying customers worth protecting and an engineering team large enough that informal habits are hard to unwind. Most early risk comes from speed: new services, third-party libraries and access granted in a hurry. A small, written program gives you control without slowing the team down.
What investors and enterprise buyers will ask for
Expect a security questionnaire before a larger contract is signed. It usually covers access control, encryption, incident response and how you handle vulnerabilities in code and dependencies. Common requests include:
- MFA on all company accounts
- Role-based access to production systems
- Written security policies
- A recent penetration test report
- A SOC 2 report, or a dated plan to get one
Answering from memory is slow and error-prone. Keep the answers in one shared document and review it each quarter.
The minimum viable security program
Start with these controls. Most are low effort and cover the attacks that hit young companies most often.
| Control | Why it matters | Effort |
|---|---|---|
| MFA on every account | Blocks common password-based takeovers | Low |
| Single sign-on for SaaS tools | One place to grant and remove access | Medium |
| Password manager and secrets vault | Keeps credentials out of code and chat | Low |
| Least-privilege cloud access | Limits damage from one stolen login | Medium |
| Secret and dependency scanning in CI | Catches known flaws before release | Low |
| Encrypted laptops with device management | Protects lost or stolen devices | Low |
| Restore drills for backups | Proves you can recover from deletion or ransomware | Medium |
| Written incident response plan | Shortens response when something goes wrong | Low |
| Offboarding checklist | Removes access the day someone leaves | Low |
Who owns what
Security fails when nobody owns it. Name one person for each area.
| Role | Owns | Does not own |
|---|---|---|
| CEO | Risk appetite, budget, security commitments to customers and the board | Writing technical controls |
| CTO | Access, pipelines, environments, code scanning | Sign-off on policy alone |
| CSO or security lead | Policies, questionnaires, risk register, incident coordination | Building infrastructure |
If you have no CSO yet, the CTO usually owns this work, with a fractional security adviser for reviews.
Securing code in the pipeline
Run these checks on every change, in this order:
- Scan every commit for secrets and block pushes that contain keys.
- Run static analysis (SAST) on each pull request and show findings in the review.
- Scan dependencies for known vulnerabilities and set fix deadlines by severity.
- Require a second reviewer for changes to authentication, payments and permissions.
- Keep staging and production on separate credentials.
- Rotate privileged keys on a fixed schedule.
Tune the rules early. If developers see too many false positives, they stop reading results. Track which findings get acted on and adjust the rest. AI-assisted scanners, including our own Orbis AppSec, aim to reduce that noise by filtering false positives and opening fix pull requests. Evaluate any tool against your own repositories before committing. For a real example of how a dependency flaw gets exploited, read our proxy-addr IP spoofing analysis.
Compliance path: SOC 2 Type I or Type II
SOC 2 is the attestation most enterprise buyers ask about. Choose the type based on the next contract you need to win.
| Question | SOC 2 Type I | SOC 2 Type II |
|---|---|---|
| What it checks | Controls are designed and in place on one date | Controls operated effectively over a period |
| Preparation | Shorter, mostly documentation and setup | Longer, requires evidence collected over time |
| Observation period | None | Commonly three to twelve months |
| Buyer value | An early signal of maturity | Stronger evidence for larger deals |
If a buyer needs proof now, start with Type I. In either case, begin collecting evidence immediately, because the Type II observation period cannot be compressed. Confirm scope and timing with your auditor.
Incident response: write the plan before you need it
A two-page plan is enough at this stage. It should name who declares an incident, who speaks to customers, and which channel the team uses if email is compromised. Work through these stages:
- Detect and declare: anyone can raise an alert, and one person confirms it.
- Contain: revoke affected credentials and isolate the systems involved.
- Investigate: preserve logs and establish what data, if any, was exposed.
- Notify: follow contractual and legal duties, with counsel reviewing wording.
- Recover: restore service from known-good backups and verify the restore.
- Review: write up the cause and assign the fixes with owners and dates.
Run a tabletop exercise once a year with the leadership team.
Common mistakes at this stage
- Buying tools before naming owners and writing policies.
- Treating the first questionnaire as a one-off instead of keeping answers current.
- Sharing credentials between staging and production.
- Enabling every scanner rule at once, so developers stop reading the results.
- Writing an incident plan only after an incident.
Frequently asked questions
Do we need a CSO at Series A? Not always. Many companies give the CTO security ownership, with a fractional security adviser for reviews, until the workload justifies a full-time hire.
How long does SOC 2 take? A Type I report can often be prepared in a few months. A Type II report also needs an observation period, commonly three to twelve months, so start collecting evidence early.
How much does a security program cost? It depends on tooling, headcount and the auditor you choose. Get written audit quotes and test scanner pricing against your own repositories.
Sources
- OWASP Top 10: the common web application risk categories.
- NIST Cybersecurity Framework 2.0: a structure for governance, identification, protection, detection, response and recovery.
- AICPA SOC 2 Trust Services Criteria: the basis for SOC 2 reports.
This guide is general guidance, not legal or audit advice. Confirm timelines and scope with your auditor before planning around them.