Tenable (Nessus, Tenable.io, Tenable One) is the world’s leading vulnerability management platform used by 30,000+ organizations to scan network infrastructure for CVEs — but as a network security scanner it has no WCAG accessibility audit, no Core Web Vitals scoring, and no front-end quality monitoring. PageGuard audits any website externally — free, no credentials required, results in 30 seconds.
ADA Title II Deadline: April 24, 2026
Government agencies, universities, and public-sector organizations using Tenable.io or Tenable.sc for infrastructure vulnerability management face ADA Title II compliance requirements for their public-facing web applications. A web server can have zero critical CVEs on its Tenable vulnerability report while simultaneously hosting web application HTML with hundreds of WCAG 2.1 AA violations — Tenable’s network scanning of server-layer CVEs reveals nothing about whether application HTML implements correct alt text, keyboard navigation, or ARIA roles. PageGuard monitors any publicly accessible web application for WCAG compliance without requiring Tenable credentials or network access.
PageGuard vs Tenable — network vulnerability scanning vs deployed website front-end quality monitoring
| Feature | PageGuard | Tenable |
|---|---|---|
| What is it? | External website health monitor — scans any deployed URL for performance, accessibility, SEO, and best practices | Tenable is a cybersecurity company headquartered in Columbia, MD, specializing in exposure management and vulnerability scanning; Tenable's flagship products are Tenable.io (cloud-based vulnerability management), Tenable Nessus (the world's most widely deployed vulnerability scanner with 2+ billion installs), Tenable.sc (on-premises vulnerability management), and Tenable OT Security (operational technology security); Tenable One is their unified exposure management platform that aggregates vulnerability, identity, and attack surface data across IT, cloud, and OT environments; Tenable scans network infrastructure, servers, cloud workloads, containers, and connected devices for CVEs, misconfigurations, and compliance violations using authenticated network-layer scanning and agent-based assessment; Tenable does not audit web application front-end quality: WCAG 2.1 accessibility compliance, Core Web Vitals browser performance metrics, or technical SEO quality are not part of Tenable's vulnerability scanning or exposure management platform |
| Free tier | ✓ Yes — unlimited one-off scans, no signup required | Nessus Essentials is a free limited edition allowing scans of up to 16 IP addresses — it scans network hosts for CVEs and misconfigurations, not web page HTML quality; Tenable.io and Tenable.sc are paid enterprise platforms with annual licensing; Tenable One (the unified exposure management platform) requires an enterprise contract; no Tenable product tier includes WCAG accessibility auditing, Core Web Vitals measurement, or technical SEO analysis of web application front-end HTML |
| Accessibility audit (WCAG / ADA) | ✓ Yes — WCAG 2.1 AA scored 0–100 with specific issue list | No — Tenable's vulnerability scanning platform performs authenticated network-layer and agent-based scans of IP-addressed hosts for CVE vulnerabilities, software version misconfigurations, default credentials, missing patches, and compliance policy violations (PCI DSS, HIPAA, CIS benchmarks); Tenable performs no analysis of web application HTML for WCAG 2.1 accessibility compliance; Tenable has no concept of alt text quality (WCAG 1.1.1), ARIA landmark structure (WCAG 1.3.1), keyboard navigability (WCAG 2.1.1), color contrast ratios (WCAG 1.4.3), or form label correctness; the WCAG accessibility quality of web applications hosted on Tenable-scanned servers is determined entirely by the application front-end code, not the server's vulnerability posture |
| Technical SEO audit | ✓ Yes — meta tags, headings, canonical, structured data | No — Tenable provides no SEO audit of web application HTML; Tenable's network scanning platform analyzes the attack surface of IP-addressed hosts for security vulnerabilities — CVE presence, open ports, service fingerprinting, and compliance posture; Tenable performs no analysis of meta title quality, canonical URL correctness, heading hierarchy, structured data validity (JSON-LD), hreflang configuration, or any other on-page or technical SEO element of web application HTML |
| Performance audit (Core Web Vitals) | ✓ Yes — LCP, CLS, FCP scored 0–100 per scan | No — Tenable does not measure browser-side Core Web Vitals (LCP, CLS, FCP, INP) for web applications; Tenable's scanning platform probes network services and hosts for security vulnerabilities using TCP/UDP service discovery, authenticated OS-level checks, and agent-based assessments — it does not render web pages in a browser context or measure DOM loading performance, layout stability, or Largest Contentful Paint timing; Core Web Vitals are browser rendering metrics dependent on frontend JavaScript execution, image loading, and layout stability in web application code, not server-level network security posture |
| Vulnerability scanning (CVE / network) | No — PageGuard is an external front-end quality monitor, not a vulnerability scanner | ✓ Yes — Tenable Nessus is used by over 30,000 organizations in 170+ countries and has identified more CVEs than any other security solution; Tenable.io scans cloud workloads (AWS, Azure, GCP), containers, web applications (DAST), and active directory for vulnerabilities using authenticated credentialed scans, unauthenticated network scans, agent-based scans, and passive network monitoring; Tenable One provides unified exposure management correlating vulnerability data, asset inventory, identity risk, and attack path analysis across the entire attack surface; Tenable.sc provides on-premises vulnerability management with continuous monitoring, asset discovery, and compliance reporting for air-gapped environments; Tenable OT Security monitors industrial control systems and SCADA environments for operational technology vulnerabilities |
| Automated website monitoring | ✓ Yes — weekly or daily scans with email alerts on score drop | No — Tenable does not perform automated front-end quality monitoring of WCAG compliance, Core Web Vitals, or SEO quality; Tenable.io and Tenable.sc provide continuous vulnerability assessment and scheduled credentialed scans of network infrastructure — generating security findings (high/critical CVEs, misconfigurations, compliance violations) for security operations teams, not accessibility regression alerts or SEO quality degradation notifications for web application stakeholders |
| AI-generated plain-English report | ✓ Yes — explains issues in non-technical language | No — Tenable provides no AI-generated front-end health report explaining WCAG accessibility, Core Web Vitals, or SEO issues in plain English for non-technical stakeholders; Tenable's Exposure AI and ExposureAI capabilities use generative AI to summarize exposure posture, prioritize CVE remediation, and explain attack paths for security teams — not to generate client-facing web accessibility or SEO quality reports for accessibility officers, marketing teams, or ADA compliance auditors |
| ADA Title II compliance monitoring | ✓ Yes — WCAG audit + alert on accessibility regression | No — Tenable does not audit or alert on WCAG compliance for web application HTML; government agencies, educational institutions, and public-sector organizations using Tenable.io or Tenable.sc for vulnerability management face ADA Title II compliance requirements for their public-facing web applications that are entirely separate from their network security posture; a government web application can have zero critical CVEs on its hosting infrastructure while simultaneously having hundreds of WCAG 2.1 AA violations in its front-end HTML; the ADA Title II deadline of April 24, 2026 requires WCAG compliance in HTML content — not patched server software; Tenable's vulnerability scanning of network hosts reveals no information about whether web application HTML implements correct alt text, keyboard navigation, ARIA roles, or sufficient color contrast |
| Works on any deployed platform | ✓ Yes — scans any URL on any hosting or platform | Tenable scans IP-addressed network hosts, cloud workloads, and connected devices using authenticated credentialed scans, agent-based scans, and passive network monitoring — it does not scan public website URLs for front-end quality; Tenable Web App Scanning (WAS) performs DAST (dynamic application security testing) of web application attack surfaces for SQL injection, XSS, and authentication vulnerabilities — not WCAG accessibility compliance, Core Web Vitals, or SEO quality; PageGuard audits any public URL regardless of what network security or vulnerability management tools the hosting organization uses |
| Independent external audit | ✓ Yes — third-party scan, shareable URL for clients/stakeholders | No — Tenable provides no built-in tool to generate a shareable external front-end health report for web application accessibility, Core Web Vitals, or SEO quality; Tenable's dashboards (Tenable.io, Tenable.sc, Tenable One) are internal security management platforms for security operations, vulnerability management, and compliance teams — not shareable accessibility or SEO quality reports for clients, procurement teams, or ADA compliance auditors |
| Instant on-demand scan | ✓ Yes — results in 30 seconds, no code changes needed | No — Tenable has no on-demand front-end health scan capability; auditing a web application for WCAG accessibility, Core Web Vitals, or SEO quality requires running dedicated front-end quality tools against the public URL; Tenable's on-demand scan capability in Tenable.io launches credentialed vulnerability scans of network hosts — not browser-based front-end quality audits of deployed web application HTML |
| Multi-site dashboard | ✓ Yes — 1–50 sites depending on plan | Tenable.io and Tenable.sc provide asset-based dashboards for tracking vulnerability exposure, patch status, and compliance posture across network hosts, cloud workloads, and containers — organized by asset group, tag, network, or business unit; these dashboards track CVE severity scores, CVSS ratings, and SLA compliance for security teams, not WCAG accessibility scores, Core Web Vitals, or SEO quality metrics for web application front-ends |
| Pricing for health monitoring | ✓ Free + from $9/mo for automated monitoring | Nessus Essentials is free for up to 16 IPs (vulnerability scanning only); Nessus Professional starts at approximately $4,000/year for unlimited IP scanning; Tenable.io starts at approximately $5,000/year for up to 65 assets; Tenable One (unified exposure management platform) is enterprise-priced based on assets; no Tenable product tier includes WCAG accessibility monitoring, Core Web Vitals scoring, or SEO audit for web application front-ends |
Get a full WCAG accessibility, Core Web Vitals, and SEO report in 30 seconds — free, no Tenable credentials, network agents, or credentialed scan access required.
Yes — PageGuard scans any publicly accessible URL from outside the organization’s network by auditing the live rendered HTML, CSS, and JavaScript. If your website is publicly accessible, PageGuard can scan it regardless of what vulnerability management tools (Tenable, Qualys, Rapid7, etc.) the hosting organization uses. No Tenable credentials, network agent installation, or credentialed scan access required.
No — Tenable Nessus performs authenticated network-layer scanning of IP-addressed hosts for CVE vulnerabilities, missing patches, software misconfigurations, and compliance violations. Nessus performs no analysis of web application HTML for WCAG accessibility compliance. Tenable has no concept of alt text quality, ARIA landmark structure, keyboard navigability, color contrast, or any WCAG 2.1 success criterion. Auditing web applications for WCAG compliance requires a dedicated external tool like PageGuard.
Yes — a server with zero critical CVEs on its Tenable vulnerability report can simultaneously host web application HTML with hundreds of WCAG 2.1 AA violations. ADA Title II and Title III compliance requirements apply to the HTML content of web applications, not the security patching status of the hosting infrastructure. Government agencies and universities using Tenable.io or Tenable.sc for vulnerability management must separately verify their web application HTML meets WCAG 2.1 AA standards. The ADA Title II deadline of April 24, 2026 applies to covered entities regardless of vulnerability management posture.
No — they serve completely different purposes. Tenable (Nessus, Tenable.io, Tenable.sc, Tenable One) is a vulnerability and exposure management platform used by 30,000+ organizations to scan network infrastructure, cloud workloads, and connected devices for CVE vulnerabilities and compliance violations — critical security tooling for identifying and remediating attack surface exposure. PageGuard is an external quality monitoring tool that audits deployed web pages for WCAG accessibility compliance, Core Web Vitals performance, and technical SEO quality. Organizations using Tenable for infrastructure vulnerability management should also use PageGuard to verify their web application HTML meets WCAG requirements — front-end accessibility quality that Tenable’s network scanning platform cannot assess.