Company lists · Data refreshed September 2026

Top 25 Vulnerability assessment firms based in the United Kingdom

RevenueBase identified 200 company matches for vulnerability assessment firms associated with the United Kingdom as of September 2026 and tracks 2,173 professional contacts across them, including 509 with verified work emails. London is the largest hub.

This list covers company matches for vulnerability assessment firms associated with the United Kingdom, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed September 22, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list RevenueBase SmartSearch · Exact Recorded Sep 22, 2026 How this list was built
200Companies
2,173Contacts tracked
509Verified emails
Explore this list → Free signup · no credit card · 500 free credits

The 25 largest vulnerability assessment firms based in the United Kingdom

Ranked by team size
Top 25 of 200 company matches for vulnerability assessment firms based in the United Kingdom, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Sep 22, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#CompanyRevenueBase SmartSearchHeadquartersEmployeesContacts
1Exact matchLeeds, United KingdomHQ recorded Sep 22, 202651-20099 contacts →

Exact match

“AppCheck is a Complete Enterprise Security Testing Solution that provides up to the minute vulnerability coverage for your entire estate.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
2Exact matchBasingstoke, United KingdomHQ recorded Sep 22, 202651-20065 contacts →

Exact match

“We’re here to provide world-leading vulnerability research and capabilities!”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
3Exact matchLondon, United KingdomHQ recorded Sep 22, 202651-20064 contacts →

Exact match

“YOU DESERVE TO BE HACKED®.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
4Exact matchLondon, United KingdomHQ recorded Sep 22, 202651-20061 contacts →

Exact match

“Intruder's continuous exposure management platform helps security, IT, and engineering teams stop breaches before they start.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
5Exact matchManchester, United KingdomHQ recorded Sep 22, 202611-5036 contacts →

Exact match

“Secarma exists to keep the world safe.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
6Exact matchCrawley, United KingdomHQ recorded Sep 22, 202611-5035 contacts →

Exact match

“ERGOS is an award-winning IT Managed Service Provider.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
7Exact matchBirmingham, United KingdomHQ recorded Sep 22, 202611-5032 contacts →

Exact match

“Aristi is a specialist provider of cyber security services with over 17 years of experience.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
8Exact matchPortsmouth, United KingdomHQ recorded Sep 22, 202611-5029 contacts →

Exact match

“Imagine a world where cyber threats are simply another challenge that you're fully equipped to handle.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
9Exact matchAltrincham, United KingdomHQ recorded Sep 22, 202611-5026 contacts →

Exact match

“Based in Manchester UK, we are an independent Cyber Security Consultancy providing Security services across a wide range of markets, from multi-national Corporate Organisations…”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
10Exact matchNewbury, United KingdomHQ recorded Sep 22, 202611-5023 contacts →

Exact match

“CyberCrowd are a market leader in the cyber security realm, offering everything from Assessment Services through to Pen Testing, CISOaaS, Certification Readiness, DPO services…”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
11Exact matchLondon, United KingdomHQ recorded Sep 22, 202611-5023 contacts →

Exact match

“Toro was founded on creating the UK's first Red Team penetration test - and then attacking hundreds of clients by hacking their systems, influencing / social engineering staff and…”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
12Exact matchLeeds, United KingdomHQ recorded Sep 22, 202611-5019 contacts →

Exact match

“Halo I.S is not just another cybersecurity organization based in the UK; we're a testament to evolution and client-centric innovation.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
13Exact matchCheltenham, United KingdomHQ recorded Sep 22, 202611-5018 contacts →

Exact match

“Hexiosec is the new name for Red Maple Technologies.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
14Exact matchWrea Green, United KingdomHQ recorded Sep 22, 202611-5018 contacts →

Exact match

“Critec Group is an independent security risk consultancy, specialising in comprehensive security risk, threat, and vulnerability analysis, as well as security mitigation design…”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
15Exact matchLondon, United KingdomHQ recorded Sep 22, 202651-20015 contacts →

Exact match

“Who We Are DataSixth delivers Cybersecurity Intelligence.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
16Exact matchLondon, United KingdomHQ recorded Sep 22, 202611-5015 contacts →

Exact match

“is an ISO 9001:2015 and ISO/IEC 27001:2022 certified, DPIIT-recognized cybersecurity company delivering structured External Vulnerability Assessment & Penetration Testing (VAPT)…”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
17Exact matchLondon, United KingdomHQ recorded Sep 22, 202611-5014 contacts →

Exact match

“Demand more from your AI & Data Security partner.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
18Exact matchHolborn, United KingdomHQ recorded Sep 22, 20261-1013 contacts →

Exact match

“Laburity: Cyber Security Research and Services Company.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
19Exact matchMilton Keynes, United KingdomHQ recorded Sep 22, 202611-5012 contacts →

Exact match

“We offer specialist CREST & CHECK Approved Penetration Testing services in order to secure our clients most critical assets.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
20Exact matchLondon, United KingdomHQ recorded Sep 22, 202611-5012 contacts →

Exact match

“At Cyber Armed Security, we protect organisations worldwide from evolving cyber threats through intelligence-driven ethical hacking.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
21Exact matchBath, United KingdomHQ recorded Sep 22, 202611-5011 contacts →

Exact match

“At Mobius Binary we care about your reputation and the loss that could result from violating your digital boundaries.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
22Exact matchLondon, United KingdomHQ recorded Sep 22, 202611-5010 contacts →

Exact match

“SecureTeam are a UK-based information security practice, specialising in all areas of cybersecurity.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
23Exact matchBirmingham, United KingdomHQ recorded Sep 22, 202611-509 contacts →

Exact match

“At Equilibrium Security, we’re a team of certified Cyber Security experts dedicated to keeping your business safe.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
24Exact matchLeamington Spa, United KingdomHQ recorded Sep 22, 202611-508 contacts →

Exact match

“Building the best Cyber Security company you've never heard of.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase
25Exact matchManchester, United KingdomHQ recorded Sep 22, 20261-107 contacts →

Exact match

“RM Information Security are a specialist penetration testing and information security consultancy based in the north of England.”

Recorded in the RevenueBase company graph · Sep 22, 2026 · View company records in RevenueBase

Showing 25 of 200 vulnerability assessment firms based in the United Kingdom

See the full list, filter by size, metro and specialty, and access 509 tracked professional contacts with verified work emails. Direct dials are available where recorded.

Free signup · no credit card

View the full list →

Vulnerability assessment firms based in the United Kingdom at a glance

As of Sep 22, 2026
23.4%Verified-email coverage
10.9Average contacts per company
1-10Median size (employees)
36.5%Largest-city concentration · London
Sep 22, 2026Page data refreshed

Companies by employee count

1-10
132
11-50
55
51-200
10
201-500
2
501-1,000
1

Email recency for this list is measured worldwide rather than for United Kingdom, so it is reported there. Company counts and contact totals on this page are exact for United Kingdom, over 200 companies.

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

Source
The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
What qualifies
Company records associated with the United Kingdom whose business descriptions match “vulnerability assessment firms” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch
Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview
The public preview omits records without a verified work email. Where headquarters information is recorded, preview rows are also filtered to this page’s location. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality
RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
Ranking
Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification
Every displayed company carries at least one verified work email. RevenueBase tracks 509 professional contacts with verified work emails across the full matched dataset. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh
This page's figures were pulled from the company graph on September 22, 2026. Lists refresh periodically as the graph is re-checked.
Record context
Company records and descriptions can change. Check the company's website for its current services and locations.

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “vulnerability assessment firms”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many vulnerability assessment firms are there based in the United Kingdom?

RevenueBase identified 200 company matches for vulnerability assessment firms associated with the United Kingdom as of September 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

Appcheck LTD tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most vulnerability assessment firms?

London leads with 73 company records, followed by Manchester (9) and Birmingham (5).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 509 professional contacts with verified work emails tracked across these 200 companies; direct dials are available where recorded.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 22, 2026.

Ready to reach these companies? Verified emails and direct dials for all 200 vulnerability assessment firms based in the United Kingdom. Start with a free account, no credit card.

Download this list →

Related lists

About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase SmartSearch, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.