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Vulnerability management platforms · October 2026 Edition
Microsoft Defender Vulnerability Management vs Tenable Nessus
Zero of fourteen models named Microsoft Defender Vulnerability Management first on the direct prompt; zero named Tenable Nessus. Microsoft Defender Vulnerability Management was named by ten of the fourteen models and Tenable Nessus by eleven and both carry 23 labels, so the shares below are directly comparable.
Named in one category this edition.
Named in four categories this edition.
First-choice share4%4%Of first choices across the direct, paraphrase, budget and scale prompts, 0 to 100.
Negative rate13%30%Negative labels as a share of the product's labels, 0 to 100.
Rank in category#6#8A position in a field of 10; printed, not drawn.
Labels2323Equal, which is what makes the shares comparable.
The two percentage rows are drawn on one 0 to 100 track, Microsoft Defender Vulnerability Management reading right to left. Rank and label count are printed, not drawn.Rapid7 InsightVM was named alongside these two in twelve of the fourteen direct answers. Rapid7 InsightVM vs Microsoft Defender Vulnerability Management · Rapid7 InsightVM vs Tenable Nessus · Tenable Vulnerability Management vs Microsoft Defender Vulnerability Management
Share is the count of first choices across the direct, paraphrase, budget and scale prompts over all fourteen models, for a mid-market B2B company; rank is within the category; every quote names the model and the prompt it came from. Both figures come from the vulnerability management platforms page.
By framing
How many of the fourteen models made each the first choice, per way of asking, and how many argued against it.
Microsoft Defender Vulnerability ManagementFirst choices, of fourteen modelsTenable Nessus
Direct00
Paraphrase011 against Tenable Nessus
Comparative001 against Microsoft Defender Vulnerability Management · 1 against Tenable Nessus
Budget-constrained213 against Tenable Nessus
Scale-constrained00
Negative002 against Microsoft Defender Vulnerability Management · 2 against Tenable Nessus
Bars are first choices, 0 to 14 each sideModels that argued againstA model can name both, so the two sides of a row do not sum to fourteen.
Across every category in the October 2026 Edition, Microsoft Defender Vulnerability Management and Tenable Nessus were named in the same answer twenty-one times, of the 73 answers naming Microsoft Defender Vulnerability Management and the 83 naming Tenable Nessus. In those answers Tenable Nessus took the first choice one time and Microsoft Defender Vulnerability Management one.
Every model, every framing
The eighty-four answers behind the chart above, one cell each: where Microsoft Defender Vulnerability Management and Tenable Nessus stood in it.
| Model | Direct | Paraphrase | Comparative | Budget-constrained | Scale-constrained | Negative |
|---|---|---|---|---|---|---|
| Claude Haiku 4.5 | | |||||
| GPT-5.4 mini | | | ||||
| Gemini 3.5 Flash | | | | | | |
| Perplexity Sonar | | | ||||
| Grok 4.1 Fast | | | | | ||
| Mistral Small | | |||||
| DeepSeek V4 Flash | | | | |||
| Llama 4 Maverick | ||||||
| Qwen 3.7 Flash | | |||||
| Kimi K2 | | | | |||
| GLM 4.7 FlashX | | | | |||
| MiniMax M2.5 | | | ||||
| GPT-6 Luna | | | ||||
| Muse Glimmer 30B | | | |
Microsoft Defender Vulnerability Management Tenable Nessus first choice named as an alternative argued againstblank: not namedEach cell is one answer, Microsoft Defender Vulnerability Management on the left and Tenable Nessus on the right.The direct prompt
The plain question, one answer per model, grouped by where Microsoft Defender Vulnerability Management and Tenable Nessus stood in it.
Neither was the first choice, one was named
3 of 14 modelsThe answer put something else first and named one of the two as an alternative.Gemini 3.5 FlashSecPod SanerNow, Vicarius vRx alternatives: CrowdStrike Falcon Spotlight, Microsoft Defender Vulnerability Management, Nucleus Security, Rapid7 InsightVM
Perplexity SonarRapid7 InsightVM alternatives: ManageEngine Vulnerability Manager Plus, Microsoft Defender Vulnerability Management, Microsoft Defender for Cloud, Qualys VMDR, Vicarius vRx
GLM 4.7 FlashXQualys VMDR alternatives: ManageEngine Vulnerability Manager Plus, Microsoft Defender Vulnerability Management, Tenable Vulnerability Management
Neither was named
11 of 14 modelsThe answer made no first choice from these two in this category.Claude Haiku 4.5Rapid7 InsightVM alternatives: ManageEngine Vulnerability Manager Plus, Microsoft Defender for Cloud, Tenable Vulnerability Management, Vicarius vRx
GPT-5.4 miniRapid7 InsightVM alternatives: Qualys VMDR, Tenable Vulnerability Management
Grok 4.1 FastRapid7 InsightVM alternatives: Intruder, ManageEngine Vulnerability Manager Plus, Qualys VMDR, Tenable Vulnerability Management
Mistral SmallRapid7 InsightVM alternatives: Intruder, ManageEngine Vulnerability Manager Plus, SureCloud
DeepSeek V4 FlashRapid7 InsightVM, Vicarius vRx alternatives: Intruder, Tenable Vulnerability Management
Llama 4 MaverickIntruder alternatives: ManageEngine Vulnerability Manager Plus, Rapid7's Insight platform
Qwen 3.7 FlashRapid7 InsightVM alternatives: Qualys VMDR, Tenable Vulnerability Management
Kimi K2Intruder, Rapid7 InsightVM alternatives: Qualys VMDR
MiniMax M2.5Rapid7 InsightVM alternatives: Intruder, Tenable One
GPT-6 LunaTenable Vulnerability Management alternatives: Qualys VMDR, Rapid7 InsightVM
Muse Glimmer 30BRapid7 InsightVM alternatives: Intruder, ManageEngine Vulnerability Manager Plus
Bold names in an answer are the products the judge labeled a first choice; a model naming several gives each of them that label. The full answer text for every row is in the record.
By buyer segment
The same question asked on behalf of a different buyer. Each standing is computed within its segment and they are never added together. The figures above are the mid-market standing, which is the one the category orders by.
Small business
Tenable Nessus leads by five points.
Tenable Nessus5%#3 of 11Microsoft Defender Vulnerability Management0%#11 of 11Mid-marketThe figures above
Level: the same share of first choices.
Microsoft Defender Vulnerability Management4%#6 of 10Tenable Nessus4%#8 of 10Enterprise
The order flips: Microsoft Defender Vulnerability Management leads at enterprise.
Microsoft Defender Vulnerability Management8%#5 of 9Tenable Nessus0%#– of 9What the models said about Microsoft Defender Vulnerability Management
Every negative label with a quote, up to three, then the highest-weighted positives, up to three. Six of seven in this category shown.
“Limitations: Feature depth drops outside Windows ecosystem; limited Linux/macOS capabilities” Kimi K2 · comparative prompt · soft negative
“they should not be your *only* vulnerability management platform” Gemini 3.5 Flash · negative prompt · soft negative
“Multi-tenant features are disappointing” DeepSeek V4 Flash · negative prompt · soft negative
“for a tight budget, I'd start with Microsoft Defender Vulnerability Management if you already use Microsoft 365 or Defender” GPT-6 Luna · budget prompt · first choice
“Microsoft Defender Vulnerability Management (free trial / included...) for risk‑based prioritization and remediation” GLM 4.7 FlashX · budget prompt · first choice
“Microsoft-heavy environment: Evaluate Microsoft Defender Vulnerability Management first if you already use Microsoft Defender for Endpoint P2” GPT-6 Luna · paraphrase prompt · alternative
What the models said about Tenable Nessus
Every negative label with a quote, up to three, then the highest-weighted positives, up to three. Six of six in this category shown.
“Avoid trying to scrape out a "Free" version of Nessus; Tenable discontinued its unlimited community scanner” Qwen 3.7 Flash · budget prompt · hard negative
“Avoid Standalone "Point-in-Time" Scanners for Enterprise VM ... Why to avoid them for enterprise VM” Gemini 3.5 Flash · negative prompt · hard negative
“scanners like older Nessus/OpenVAS versions criticized for inaccurate Windows scans or signature mismatches” Grok 4.1 Fast · negative prompt · soft negative
“the best starting point is Nessus Essentials (free) + a free vulnerability feed for on‑prem scanning” GLM 4.7 FlashX · budget prompt · first choice
“I'd recommend Tenable Nessus Professional as the starting point” Grok 4.1 Fast · paraphrase prompt · first choice
“useful for getting started with proven scanning technology, with the limitation of scan limits and lack of centralized reporting” Muse Glimmer 30B · budget prompt · alternative
Also compared
Rapid7 InsightVM vs Microsoft Defender Vulnerability ManagementRapid7 InsightVM vs Tenable NessusTenable Vulnerability Management vs Microsoft Defender Vulnerability ManagementTenable Vulnerability Management vs Tenable NessusIntruder vs Microsoft Defender Vulnerability ManagementIntruder vs Tenable NessusQualys VMDR vs Microsoft Defender Vulnerability ManagementQualys VMDR vs Tenable NessusManageEngine Vulnerability Manager Plus vs Microsoft Defender Vulnerability ManagementManageEngine Vulnerability Manager Plus vs Tenable NessusMicrosoft Defender Vulnerability Management vs Vicarius vRxVicarius vRx vs Tenable NessusAll twenty-eight head-to-head pages and the full vuln management standing
Comparisons are drawn for the top eight products in each category, each against each. The output is the models' output; nothing here is a recommendation by the index.