Intruder
Intruder scans a company's internet-facing systems, web apps, cloud accounts and, on higher plans, internal devices for weaknesses, and sorts the results so a small team knows what to fix first.
CyberReviewed Editorial Team · Updated · intruder.io
Company details
- Score
- 7.6/10Ranked 5 of 12 (tied)
- Category
- Vulnerability management
- Founded
- 2015
- Headquarters
- London, England
- Leadership
- Chris Wallis, founder and CEO
- Customers
- 3,000+
- Pricing
- Free tier; Cloud from $239 per month billed annually
- Best fit
- Small and mid-size teams without a dedicated vulnerability analyst
Our take
Intruder is easy to justify for small and mid-size companies that need regular vulnerability scanning and clear guidance on which findings to fix first. Large enterprises with thousands of internal assets and complex workflows will likely outgrow it.
Scores by criterion
| Criterion | Score |
|---|---|
| Pricing transparency | 9 |
| Product scope and fit | 7 |
| Company durability | 6 |
| Evidence of adoption | 7 |
| Ease of adoption | 9 |
| Overall score (average of the five) | 7.6 |
Each criterion is defined on our methodology page.
Scanning with fewer alerts
Intruder scans external infrastructure, web applications, APIs, cloud accounts and container images for vulnerabilities and misconfigurations, and its higher plans add agent-based scanning of internal servers and employee devices.1 Founder Chris Wallis started the company after noticing that vulnerability tools were good at finding issues but poor at prioritizing them, and the product's design still centers on cutting noise for small teams.2 Recent additions include attack surface management in 2024 and cloud security in 2025, along with an AI analyst the company calls GregAI.2
Plans from free to Pro
Intruder posts its prices. A free plan covers weekly external vulnerability scans of up to five infrastructure targets, weekly checks of one cloud account and two container images. The Cloud plan is listed at $239 a month billed annually ($2,870 a year) and the Pro plan at $399 a month billed annually ($4,790 a year), with the annual option saving 20% over monthly billing; Enterprise is quoted.1 Cloud and Pro prices combine a base fee with a per-target charge, a license stays in use for 30 days after a target is scanned, and AI-assisted web application pentests start at $3,500 per test.1 A 14-day trial includes Cloud plan features and five target licenses.1
From one customer to 3,000
Wallis, a former ethical hacker who also worked on the defensive side for critical national infrastructure, founded Intruder in 2015 and took its first paying customer that year.2 It joined GCHQ's Cyber Accelerator in 2017, reached 2,000 customers in 2022 and was included on Deloitte's UK Technology Fast 50 in 2023 as the fastest-growing cybersecurity company in the country.2 It now reports more than 3,000 customers.2
Enterprise scanners and pentest vendors
The established vulnerability management vendors offer broader enterprise features, deeper internal scanning and more integrations, at higher cost and complexity. Intruder has fewer features and is simpler to run. It also overlaps with pentesting companies: its pentest offer starts at the same $3,500 per test as Cobalt's promotional autonomous pentest, while Horizon3.ai runs autonomous attacks against internal networks.
Large internal estates
Organizations with very large internal estates, strict on-premises scanning needs or a mature vulnerability management team working across thousands of assets are better served by enterprise platforms. For companies that need to show customers and auditors regular scanning for SOC 2, ISO 27001 or Cyber Essentials, Intruder covers that requirement.1
What customers say
Quoted word for word from public reviews and posts on Reddit and TrustRadius, retrieved October 21, 2026. Each quote links to the review or post it comes from.
Where it helps
When the infrastructure landscape and risk profile is not well known and is legacy, Intruder can scan and automate reporting on open security risks, as well as coordinate responses.
We have been using Horizon3.ai and intruder.io to limit vulnerabilities, both where simple to setup and have helped us find external and internal vulnerabilitues that ...
Where it falls short
Reports could contain more detail.
