crt.sh vs FestIn: Side-by-Side Comparison (2026)
Features, pricing, ratings, and pros & cons — compared head-to-head.
crt.sh is a free external attack surface management tool. FestIn is a free external attack surface management tool. Compare features, ratings, integrations, and community reviews side by side to find the best external attack surface management fit for your security stack.
CST VerdictBased on our analysis of NIST CSF 2.0 coverage, core features, integrations, company size fit, here is our conclusion:
Security teams doing threat intelligence or domain monitoring should use crt.sh as a free, fast way to spot certificate issuance anomalies that signal domain takeover or phishing campaigns before they scale. Certificate Transparency logs index roughly 15 billion certificates, giving you real-time visibility into what's been legitimately issued against your domains and competitors' infrastructure. Skip this if you need automated alerting or integration into your SIEM; crt.sh is a lookup tool, not a monitoring platform, and catching malicious certificates requires manual checks or custom scripting.
AppSec and cloud infrastructure teams hunting for S3 misconfigurations tied to their own domains should start with FestIn; it's free, which means you can run it immediately without budget cycles, and the DNS reconnaissance approach catches buckets that simpler bucket-enumeration tools miss. The 230 GitHub stars suggest active maintenance and community validation of the crawling methods. Skip this if your threat model requires continuous monitoring or remediation workflows; FestIn is a point-in-time discovery tool, not a compliance scanner.
