Creators of the world's largest
Subdomain & Exploit Database

A.R.P. Syndicate builds and operates internet-scale intelligence datasets. Rather than reselling another vendor's feed, we run our own discovery infrastructure and publish the results through APIs that are free to query and priced flatly when you need them at scale.

Subdomain & Shadow IT Intelligence

Subdomain Center maps hosts across more than a billion registered domains. Discovery does not rely on DNS brute force — it combines web-scale crawling, real-time Certificate Transparency ingestion and embedding-based host correlation, which surfaces infrastructure that wordlists and certificate logs alone do not reach, including hosts sitting behind a reverse proxy.

In an independent benchmark, it returned more than twice as many valid subdomains as the next-best free source. The dataset is integrated into BBOT, theHarvester and OWASP Amass.

Vulnerability & Exploit Intelligence

Exploit Observer resolves the identifier sprawl around vulnerabilities. A single real-world flaw typically accumulates a CVE number, a GHSA advisory, vendor bulletins, exploit modules and entries in national registries — all describing the same thing. Our VEDAS system clusters them under one identifier, so a single lookup returns the complete picture rather than one fragment of it.

Coverage deliberately extends past the English-language advisory ecosystem to include CNNVD, CNVD, BDU (Russian FSTEC), JVNDB and EUVD — registries that publish independently of MITRE and that most Western vulnerability feeds omit entirely.

How access works

Both APIs are free to query with no account and no key, subject to result caps and rate limits. Paid keys remove those limits rather than unlocking different data — you can evaluate the full quality of either dataset before speaking to anyone. Both are queryable from the command line via puncia, our open-source CLI.