Search 2.0 Quick Start Guide
Censys Search makes Internet-facing hosts and certificates searchable, just like Google makes websites searchable.
The best way to get started with Censys Search is to prepare a list of questions you want to answer. Each question you’re asking will be expressed as one or more search queries written in the Censys Search Language.
When you write a query, Censys evaluates every host or cert in the dataset you’re searching for matches and returns that list to you.
Host Queries: Questions About Hosts
Here’s an example query of hosts.
This query (expressed as a field, value pair):
asks the question:
"Which hosts (and virtual hosts) are presenting a certificate during a TLS handshake that has a common name containing
Here’s what that question and answer looks like on the the Search web UI.
Host Search Result Settings
Censys Search offers several settings for search results.
Sort Order Options
Choose from several options for the order of results from your search query:
Relevance — Orders results from most closely matching your search query to least closely matching.
Ascending — Orders results from lowest numerical IP address to highest.
Descending — Orders results from highest numerical IP address to lowest.
Random — Randomizes results matching your search query.
Number Hits Per Page
Choose how many hits to display on each page of search results:
Choose whether to include or restrict results to virtual hosts, which model hosts identified by both an IP address and name.
Certificate Queries: Questions About Certificates
Here’s an example for certs. This query:
parsed.validity.end: [2022-11-03 TO *} and parsed.signature.self_signed: true and not parsed.subject.common_name: * and metadata.source: scan and parsed.extensions.basic_constraints.is_ca: false
asks the question:
"Which unexpired, self-signed, nameless certificates that are not used for signing other certificates were found while Censys was scanning hosts?"
Here’s what that looks like in the web UI:
Note about searching certificates: There are some small differences in the Search Language used to write queries against certificates vs. hosts.
Use the Reports feature to understand the distribution of values for a field across a set of hosts or certificates.
To create a report, first provide criteria for hosts or certificates to evaluate in the search bar using the Censys Search Language.
Then click the Report tab on the right side of the results page.
On the report page, type the name of the field whose values you want to see a breakdown for, and select the number of buckets to aggregate values into.