Passive scanning
Passive vulnerability scanning, safe to run in production.
No payloads, no brute forcing, no state changes. Just observation of what your live app already exposes. Run it against prod without a war room.
How passive scanning works
A polite scan you can run any time of day.
Read-only
No state changes, ever
Passive scans don't submit forms, don't write data, don't trigger transactional flows. The app behaves exactly the same after the scan as before.
No payloads
No exploit attempts in default mode
Passive scans observe what the server returns. No SQL-injection probes, no XSS payloads, no buffer-overflow attempts. Safe for prod.
Rate-limited
Won't take down your site
Scans are throttled to avoid load spikes. Slower than an unthrottled scan, but your service stays up.
Same surface
Looks like a regular visitor
Default scan behaves like a polite browser. Reads pages, reads headers, checks TLS, runs DNS lookups. Nothing your CDN would flag.
Deep findings
Catches the categories that matter
TLS, headers, cookies, CORS, DNS, email auth, network exposure, web hygiene. The categories that fail audits, all passively detectable.
Continuous AI pentesting
Active testing that keeps running
SQL injection, XSS, broken access control and IDOR only show up under active testing. An AI pentest covers them, on a schedule or on demand from the dashboard. Paid in credits, non-destructive.
What we observe
The signal you'd never get from logs alone.
- ✓TLS handshake details, cipher suite strength, certificate chain validity
- ✓Every security header the app returns, plus what's missing
- ✓Cookie attributes on every Set-Cookie
- ✓DNS records relevant to security: SPF, DKIM, DMARC, CAA
- ✓Network surface: open ports (non-intrusive), subdomain takeover candidates
- ✓Page-level web hygiene: vulnerable JS libraries, mixed content, framework leakage
Beyond the surface
What a passive scan can't tell you.
A passive scan shows what your app exposes. It can't tell you whether any of it can be exploited, because finding that out means sending requests that exercise the app's logic. That's the job of a continuous AI pentest. AI agents test your web app and APIs the way an attacker would, looking for SQL injection, broken access control, IDOR and business-logic flaws. Findings are checked against your live app before they're reported, and confirmed ones come with the request and response that prove them.
The pentest can rerun on a schedule you set, and each run marks earlier findings as new, still open, resolved or regressed. See how Barrion's AI pentesting works, or read what continuous pentesting is.
FAQ
Passive vulnerability scanning, explained.
What's the difference between passive and active vulnerability scanning?
Passive scanning observes what your live application already exposes, TLS handshakes, security headers, cookies, DNS records, network surface, without sending crafted payloads or interacting with state-changing routes. Active scanning sends test inputs to find bugs that only show up under interaction (e.g. SQL injection payloads, XSS probes, authentication bypass attempts). Passive is safe to run against production continuously. Active testing is what Barrion's AI pentests do, against a scope you approve before any traffic is sent.
What categories of issue can passive scanning actually catch?
Passive scanning is the right tool for the OWASP A02 (Cryptographic Failures), A05 (Security Misconfiguration), A06 (Vulnerable and Outdated Components), and A09 (Security Logging and Monitoring Failures) categories. It also catches DNS and email-authentication issues (SPF, DKIM, DMARC, CAA), network exposure (open ports, subdomain takeover candidates), and framework leakage (server headers, debug pages reachable from the internet).
Will passive scanning trigger my WAF or rate limits?
Generally no. Passive scans look like a polite browser to your CDN and WAF, they read pages, read headers, do DNS lookups, check certificate chains, and check which common ports accept a TCP connection. Rate-limited and throttled by default. If you run a particularly strict WAF rule set, the scanner's source IPs can be allowlisted, but most sites need no configuration change.
If passive scanning is safe, why does anyone use active scanning?
Because some of the most impactful vulnerabilities only show up under interaction. SQL injection, broken access control, IDOR, business-logic abuse, these require the scanner to send requests that exercise the application's logic, not just observe its surface. Active scanning is essential for those categories. Barrion's recommendation is passive monitoring as the always-on baseline, plus AI pentests that rerun on a schedule or on demand, with an extra run before an audit or a major launch.
Can passive scanning be used as compliance evidence?
Yes for the relevant control families. SOC 2 CC7 (System Operations), ISO 27001 Annex A 8.16 (Monitoring activities), PCI DSS Requirement 11 (Regularly test security systems and processes), and NIS2 ongoing-risk-management requirements can all use automated passive scanning as ongoing-monitoring evidence, though your auditor decides what's accepted. For PCI DSS Requirement 11.4 (penetration testing), passive scanning is only supplementary. For the pentest itself, Barrion's AI pentest produces an audit-ready report in which confirmed findings come with the request and response that prove them.
Run a passive scan on production.
It's read-only and safe for live apps, and the first report takes about 60 seconds. Sign up to schedule recurring scans.