A NOTE ON SEVERITY
Not every item on this list carries the same level of risk. Some are the kind of finding that stops a deal. Others are serious but manageable. We have tried to make that distinction clear under each gap, but the right answer for your company always depends on your specific context.
After working across dozens of early-stage companies, patterns emerge. The specific technology stacks change, the products are different, the teams have different backgrounds — but the security gaps that show up right before a Series A are remarkably consistent. Not because startups are careless, but because the pressures of early-stage growth push decisions in predictable directions.
This list is drawn from real assessment findings across pre-A companies. Each gap here is one we encounter regularly, and each one is fixable. The goal is not to alarm anyone — it is to give founders and engineering leads a concrete picture of where to focus attention before these issues surface in a due diligence process or, worse, an incident.
- Hardcoded credentials and secrets in source code
API keys, database passwords, private tokens, and cloud credentials left inside application code or configuration files. This happens most often when developers are moving fast and reach for the simplest solution to get something working. The credential gets committed to a repository, and even if it is removed later, version control history retains it. In companies using shared repositories, a single exposed credential can hand an attacker access to your entire cloud environment.
Why it matters: In a penetration test, this is often the first place we look and one of the most common findings we make. Exposed credentials in a GitHub repository — even a private one — can be discovered through automated scanning tools that bad actors run continuously against public and leaked code
- Overprivileged cloud roles and service accounts
Cloud providers like AWS, GCP, and Azure make it easy to get things running quickly by granting broad permissions. The problem is those permissions rarely get trimmed back. A Lambda function that only needs to read from one S3 bucket ends up with permissions to read everything. A service account created for a specific task ends up with administrator-level access. Over time, the gap between what your cloud resources need to do and what they are actually allowed to do grows into a significant attack surface.
Why it matters: If an attacker compromises any component in your environment, overprivileged roles determine how far they can move from that initial foothold. The difference between a minor incident and a major breach often comes down to whether your IAM policies followed the principle of least privilege.
- Authentication that is easy to bypass or brute force
Weak authentication shows up in a few different forms. Missing rate limiting on login endpoints makes brute force attacks trivial. Absence of multi-factor authentication on administrative interfaces leaves them exposed to credential stuffing. Password reset flows that rely on predictable tokens or do not properly expire old sessions create exploitable paths that look legitimate to your logs. Any one of these is a real problem. All three together, which is not unusual, means your front door has several keys hidden under the mat.
Why it matters: Authentication weaknesses are among the most actively exploited vulnerabilities in web applications. They require no sophisticated technique — just automated tools and patience. Enterprise buyers with security review processes will ask specifically about MFA and account security controls. - Missing or misconfigured security headers
HTTP security headers are a set of instructions your application sends to the browser telling it how to behave. Headers like Content-Security-Policy, Strict-Transport-Security, X-Frame-Options, and others prevent a range of common attacks including cross-site scripting, clickjacking, and protocol downgrade attacks. They take minutes to configure correctly and have no meaningful performance impact. Despite that, they are absent or misconfigured in the majority of early-stage applications we assess.Why it matters: While missing headers are rarely a critical standalone finding, they are consistently flagged in compliance reviews, enterprise vendor assessments, and automated security scanners that prospects or investors might run against your domain. They are also easy to fix, which makes their absence harder to explain.
- Exposed administrative interfaces and internal tooling
Development databases, admin panels, internal dashboards, and monitoring interfaces that were set up quickly and never properly locked down. In many cases they are protected only by a weak password, or by an assumption that nobody would find them because the URL is not obvious. They are found anyway — either through subdomain enumeration, directory scanning, or simply by someone browsing through your application looking for anything unintended. The Kibana dashboard with no authentication, the Grafana instance accessible without a VPN, the Django admin panel on a predictable path with default credentials — these appear in real assessments.
Why it matters: Administrative interfaces typically have access to your most sensitive data and your most powerful operations. They are exactly what an attacker looks for after finding an initial foothold. They are also exactly what a sophisticated investor’s technical team will probe during due diligence.
The gaps that show up in due diligence are almost never exotic. They are the same predictable findings, at company after company, that nobody had time to address. - Inadequate logging and no alerting
Most early-stage startups have some logging in place. What they rarely have is logging that is actually useful for detecting or investigating a security incident. Logs that do not capture authentication events, that do not record what data was accessed, that are stored in the same environment they are monitoring, or that nobody is watching in real time — these are not a security control, they are a record-keeping function. Without meaningful security logging, you have no way to know whether your systems have already been compromised.
Why it matters: During a security assessment, the absence of proper logging is itself a significant finding. More practically, in the event of a breach, investors, customers, and potentially regulators will ask what you knew and when you knew it. Without logs, that question has no good answer.
- Third-party dependencies with known vulnerabilities
Modern applications are mostly composed of open-source libraries and third-party packages. Most startups are not tracking whether the specific versions of those packages contain known vulnerabilities, and even fewer have a process for updating them on a regular cadence. A package that was secure when you first added it to your project may have had a critical vulnerability disclosed three months ago. If you are not monitoring for that, you do not know about it.
Why it matters: Supply chain attacks have become a primary attack vector. Dependency vulnerabilities were behind several high-profile breaches in recent years, and automated tools make it easy for attackers to identify applications running vulnerable library versions. Software composition analysis — scanning your dependencies against known vulnerability databases — is a relatively low-effort control that most startups have not put in place.
- Insecure data storage and transmission
Data that should be encrypted at rest is stored in plaintext. Sensitive fields in a database have no additional protection beyond the database password. Internal services communicate over unencrypted channels because it felt like overkill during initial development. API responses return more data than the client actually needs, leaking fields that were never intended to be exposed. Each of these is a version of the same underlying issue: data handling was designed for functionality first and security second, with the security piece never revisited.
Why it matters: Data handling findings are among the most consequential in any security assessment from a regulatory and reputational standpoint. If customer data, payment information, or health records are involved, the exposure creates liability that goes well beyond a failed security review.
- No defined security ownership or incident response plan
This one is structural rather than technical. In most early-stage startups, security is everyone’s responsibility in theory and nobody’s responsibility in practice. There is no defined owner, no documented process for handling a security incident, and no playbook for what to do if something goes wrong. This does not show up in an automated scan, but it surfaces quickly in any serious assessment or due diligence conversation.
Why it matters: When an incident happens — and the question is when, not if — the absence of a defined response process turns a manageable situation into a chaotic one. Investors and enterprise customers increasingly ask about incident response during the evaluation process, and the absence of any plan is a flag that is hard to dismiss.
- Untested disaster recovery and backup integrity
Backups exist. They have never been tested. The recovery procedure is documented somewhere, but it has never been run against a realistic failure scenario. This is the state of most early-stage companies, and it is understandable — restoring from backup is not a high-visibility activity, and it is easy to defer. The problem is that backups you have never tested are backups you cannot rely on. A ransomware event, a corrupted deployment, or a cloud provider incident becomes dramatically worse when your fallback is itself untested.
Why it matters: Investors conducting technical due diligence will ask about your RTO (recovery time objective) and RPO (recovery point objective). Beyond that, business continuity risk is a direct concern for enterprise customers who are evaluating how much they can depend on your platform. Untested recovery is essentially an undisclosed operational risk.
What to do with this list
None of these gaps are exotic. None of them require a large security team to address. What they require is a systematic approach: understanding which of these apply to your specific environment, prioritizing by actual business risk, and working through remediation in a documented, verifiable way.
Running through this list is a reasonable starting point for a self-assessment. The next step beyond that is having an independent third party validate which of these gaps actually exist in your environment and how exploitable they are in practice. That is the difference between knowing you should probably look at your IAM policies and knowing specifically which role has an over-broad permission that an attacker could chain into a full environment compromise.
The good news is that the majority of startups that address these gaps systematically before their A round find that the process itself builds confidence internally as much as it does externally. Your team knows where things stand. Your investors see a company that takes risk seriously. Your enterprise prospects have documentation they can point to in their own vendor reviews.
A systematic approach to these ten areas will put most early-stage startups ahead of the majority of their peers from a security standpoint.
The next piece in this series focuses on startups preparing for fundraising specifically — how to use a pentest report and an attestation letter to tell a credible security story to investors and enterprise customers before they ask the questions you are not ready for yet.
