Penetration Testing
Web, API, mobile and internal network tests run by OSCP/OSCE-certified humans, not just scanners.
Offensive security · 24/7 SOC · Incident response
We think likeattackersso you don't have to.
Sentinel is a team of 64 ethical hackers, detection engineers and responders protecting fintech, health and SaaS companies across Europe and North America.
SOC status: all systems nominalevents triaged today: 2,481,906
Trusted by security teams at
NorthwindKestrel PayHalcyonMedivaultOrbitlyBrightline
What we do
All services Six disciplines. One security partner.
Buy a single test or let us run your entire security programme. Every engagement is led by a named principal, never a sales engineer.
Red Team Operations
Goal-based adversary simulation: phishing, physical entry and lateral movement against your real defences.
24/7 Managed Detection
Our Lisbon and Austin SOC watches your endpoints, identity and cloud logs around the clock.
Incident Response
Retainer-backed responders on a call within 15 minutes and on site within 24 hours, worldwide.
Cloud Security Review
AWS, Azure and GCP posture reviews mapped to CIS benchmarks, with Terraform-ready fixes.
Compliance Readiness
SOC 2, ISO 27001, PCI DSS and NIS2 gap analysis plus the evidence pack auditors actually want.
analyst: on shiftqueue: 4p1 sla: 15m
Managed detection
A SOC that actually picks up the phone.
Alerts are triaged by people who know your environment. No ticket ping-pong, no 3 a.m. emails you will read at 9.
- Detection rules tuned to your stack in the first 30 days
- Human-verified alerts: 96% fewer false positives than raw EDR
- Containment actions pre-approved, executed in minutes
- Monthly threat briefing with your named analyst
By the numbers
Measured, reported, proven.
11mmean time to respond (2026 YTD)
1,240+penetration tests delivered
0clients breached while on MDR
97%contract renewal rate
How an engagement runs
From first call to closed findings.
Scope
A 45-minute call with a principal to agree targets, rules of engagement and success criteria.
Attack
We test with the same tradecraft real groups use, with daily status updates in a shared channel.
Report
Executive summary, reproducible findings and fixes your developers can merge the same week.
Retest
Free retest within 60 days, so the final report shows what is fixed, not just what was found.
Clients
Heard on the bridge call.
They found an IDOR in our payments API that two previous vendors missed. The fix guidance was good enough to ship in a day.Hannah ReiterCTO, Kestrel Pay
Saturday, 2 a.m., ransomware on a file server. Sentinel had it contained before our own on-call engineer was awake.Tomás IbarraHead of IT, Medivault Clinics
We passed SOC 2 Type II on the first attempt. Their evidence checklist alone saved us a quarter.Grace LiuVP Engineering, Orbitly
Free · 3 minutes · no agent install
Find out what attackers already see.
Run our external threat check on your domain. We look at exposed services, leaked credentials, email spoofing and TLS hygiene, then send a plain-English report.