Application and system security
Business applications are a standing target. We find where the vulnerabilities are, tell you which ones matter, and fix them before someone else finds them first.
Where application vulnerabilities actually come from
Most of what turns up in an application audit is not exotic. An admin panel reachable from the open internet. A dependency three major versions behind. A file upload that trusts the filename it is given. An API endpoint that checks whether you are logged in, but not whether the record you asked for belongs to you.
Boring problems. They are also the ones that cause incidents, because finding them at scale is cheap and fully automated. Nobody is studying your application personally. Something is sweeping the internet for a known flaw in a known version, and your server either answers or it does not.
This shapes the order we work in. Start with the problems that are common, cheap to test for and cheap to exploit. Work down from there. If time runs out, it should run out on the obscure cases.
The application is not the whole surface
An application never exists on its own. It runs on a server, talks to a database, calls third-party APIs, and is deployed by a pipeline that holds credentials. A review that stops at the code misses most of what an attacker can touch.
So we go wider than the codebase. The application itself: authentication, authorization, input handling, sessions, file handling. The configuration around it: framework and server settings, exposed ports, admin interfaces, TLS, security headers. The dependency tree. And the integration points, where permissions have a habit of accumulating. API keys are the clearest example. One gets issued for a single integration, scoped broadly because that was quicker, and then nobody rotates it for four years.
Staging environments deserve a specific mention. They are frequently a copy of production with real data, weaker passwords and no monitoring, sitting on a subdomain that was never taken down.
Finding is the easy half
Anyone can run a scanner. The scanner produces a list, most of the list is noise, and none of it comes with a sense of what matters for your system.
The useful work is triage. For every finding, three questions: can it actually be reached in your setup, what does it get someone if it works, and what does the fix cost. The classes we consistently find worth the attention are:
Authorization gaps. The endpoint confirms identity but not entitlement. Change an ID in the URL, get someone else's data. Scanners rarely catch this because it requires understanding what the data means.
Outdated dependencies. Not all of them matter. The ones that matter are in code paths that handle untrusted input.
Configuration drift. Something was opened up during a migration or an incident, and never closed again.
Credential handling. Keys in repositories, in environment files committed by accident, or shared across environments so a staging leak becomes a production problem.
Missing rate limits. Login, password reset and search endpoints that will happily accept several thousand attempts a minute.
Fixes that hold
A patch closes one hole. It does not stop the same class of hole reappearing in next quarter's feature.
Where it is proportionate, we prefer changes that make the safe path the default: authorization enforced centrally rather than remembered per endpoint, secrets loaded from one managed source, dependency alerts wired into your build so the next advisory reaches a developer instead of nobody. That kind of change is more work up front and considerably less work every month afterwards.
Not everything justifies it. Sometimes the right answer is to update the library, verify the fix and move on.
What this does not solve
Application security is one layer. It will not help if an employee laptop is compromised and an attacker arrives holding a valid session, which is what endpoint protection is for. It will not help if someone deletes the production database, which is what backups are for. And it is a point-in-time picture, accurate on the day it was written.
We would rather say that plainly than sell a review as a guarantee. The honest version is that a good audit removes the cheap, automated attacks almost entirely, and raises the cost of the rest enough that most attackers move on to a softer target.
What you get
Application and server configuration audit
A structured review of how your application and the machines it runs on are set up, covering authentication, session handling, exposed interfaces, TLS and security headers.
Dependency and patch review
We map your dependency tree against known vulnerabilities and separate the ones that are actually reachable in your setup from the ones a scanner flagged but nobody can exploit.
API and integration hardening
Authorization checks on every endpoint, scoped keys instead of shared ones, and rate limits where an endpoint can be hammered. Integrations are where permissions quietly accumulate.
Protection against automated attacks
Defences against the traffic that never sleeps: credential stuffing, brute force on login and admin paths, injection attempts and cross-site scripting.
Prioritised findings report
Every issue with a plain-language explanation of what it lets someone do, how likely it is, and what fixing it costs. Ordered so you can start at the top and stop when the risk is acceptable.
Remediation support
We can hand the report to your developers, work alongside them, or implement the fixes ourselves. A report nobody acts on has not improved anything.
How we work
- 01
Map the attack surface
We inventory what is actually exposed: domains, subdomains, admin panels, APIs, staging environments left running. Forgotten systems are a common starting point for an attacker.
- 02
Test and review
Automated scanning for the known classes of problem, then manual review of authorization logic, business flows and configuration, which is where scanners are weakest.
- 03
Triage against your context
Findings are ranked by reachability and blast radius in your environment, not by a generic severity score. A theoretical issue in an internal tool is not an emergency.
- 04
Fix in priority order
Patching, configuration changes and code fixes, starting with anything reachable from the internet without credentials. Each change verified before it is called done.
- 05
Set up the recurring checks
Dependency alerts, scanning in your build pipeline and a schedule for the next review, so the picture does not go stale the week after we leave.
Tools and technology
Where a solid open-source tool exists, we choose it over a closed one. No lock-in to a single vendor, and costs you can actually predict.
- OWASP ZAP
- Semgrep
- Trivy
- Nuclei
- Gitleaks
- OSV-Scanner
- Sentry
- Burp Suite
- Dependabot
- GitHub Actions
- Cloudflare WAF
- Vercel WAF
Frequently asked questions
More services in this category
Network and infrastructure security
Most infrastructure is secured in theory. We make access match what people actually need, and split the environment so a problem in one place does not become a problem everywhere.
Backups and data recovery
A backup only counts if you can restore from it. We build backup systems that run automatically, survive an attack on the main environment, and get tested by actually restoring the data.
Risk analysis and recommendations
Not every company needs the same level of protection. We work out what can realistically go wrong in your business, where the weakest points are, and what is worth securing first.
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