Vulnerability scanner
Invadel vs Nessus
Nessus is one of the most widely deployed vulnerability scanners, and it is very good at what it does: finding known issues fast across many hosts. It is not a penetration test, and most compliance frameworks require both.
The models
How each one works
Nessus
As of Sep 2026, Nessus, from Tenable, is scanning software sold as an annual subscription in Professional and Expert editions. It identifies known vulnerabilities, missing patches, and misconfigurations across operating systems, devices, and applications on a schedule you set.
Invadel
A tester takes what a scanner finds, plus everything it misses, and works out what an attacker could actually reach. The output is proof and a prioritized fix plan, not a list of CVEs.
Side by side
Invadel compared with Nessus
| Dimension | Nessus | Invadel |
|---|---|---|
| What it is | Licensed scanning software you operate | A delivered manual engagement |
| Finds | Known CVEs, missing patches, misconfigurations | Chained attack paths, logic flaws, authorization gaps |
| False positives | Your team validates the output | Every finding manually verified before delivery |
| Proof of exploitability | Not provided | Demonstrated and evidenced |
| Independence | Self-operated | Independent third party, which auditors require |
| Cost model | Annual software subscription | Fixed price per engagement, published on the pricing page before you talk to anyone |
Facts about Nessus checked in against its own website. Spot something out of date? Tell us.
An honest read
Which one should you pick
We would rather you choose correctly than choose us. Here is where each option genuinely wins.
Choose Nessus when
- You need recurring coverage across hundreds or thousands of hosts.
- Your priority is patch hygiene and knowing when a new CVE affects you.
- You have staff to tune the scanner and triage its output.
Choose Invadel when
- An auditor or customer asked for an independent penetration test.
- You need to know which findings actually chain into a breach.
- You want the false positives removed before you see the report.
Where to start
The engagements buyers compare here
Vulnerability Scanning Services
Managed scanning validated by an analyst, which cuts false positives down to real, ranked risk you can act on at once. From $1,500 per scan.
From $1,500
External Network Penetration Testing
Testing of your internet-facing perimeter, from exposed services and VPN gateways to mail and cloud edges, with a free retest, from $4,200.
From $4,200
Internal Network Penetration Testing
Testing from an assumed foothold inside your network: Active Directory attack paths, lateral movement, and segmentation, from $6,000.
From $6,000
What drives each price: Vulnerability Scanning cost guide, External Network cost guide, Internal Network cost guide.
01Can we just send you our Nessus output?
We will happily start from it. Validating and prioritizing existing scanner output is part of our vulnerability assessment, which starts at $1,500 with a human analyst removing false positives.
02Does a scan meet PCI DSS?
Only part of it. Requirement 11.3 covers scanning and 11.4 covers penetration testing, so you need both. See our PCI DSS page.
03Do you use scanners?
Yes, as reconnaissance. They map the surface quickly; the findings that matter come from a tester working by hand afterward.
Compare us on your actual scope
Tell us what you need tested and we will price it against whatever quote you are holding. Fixed scope, fixed price, free retest.
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