OSINT Radar
Domain OSINT Unverified

CertObserver CT search

certobserver.com

Finds certificates and subdomains using Certificate Transparency data. An alternative to crt.sh that presents the information a bit differently.

Free Open Source
Open tool

Pivot map

You have domain
You get dns records subdomains whois records

Use this map to decide whether CertObserver CT search accepts the lead you are holding, and what kind of lead it may return for the next step.

Pivot from here

Outputs from CertObserver CT search can become inputs for the next tool. These are the most relevant follow-on pivots in the library.

Investigator Use

CertObserver CT Search is a free tool for finding unexpired TLS certificates recorded in public Certificate Transparency logs. It supports exact domains, wildcard coverage, and subdomain searches, with results grouped and sorted by certificate attributes, issuer, expiration, or logging date.

Before You Pivot

Record Context

Capture the target, search terms, and why this source is relevant before you leave the page.

Preserve Evidence

Archive volatile pages, save screenshots, and keep timestamps for anything that may change.

Corroborate

Treat one tool as a lead source. Confirm important findings with independent sources.

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