For SOC teams

Work the top of the queue, not all of it

A SOC queue is rarely short of alerts. It is short of an ordering. Most of what fires against an internet-facing service is background radiation, and the cost of that is not the noise itself but the twenty minutes an analyst spends proving an address is boring. CTIF attaches a 0 to 100 hostility score, the network that owns the address and the attacks we watched it commit to every event, so the queue sorts itself and the boring ones are visibly boring.

What it changes on a Tuesday

Three things, concretely. Triage stops being sequential, because the score is a sort key. Enrichment stops being a browser tab, because the ASN, geolocation, Tor and CDN status and MITRE ATT&CK mapping arrive with the alert. And a verdict stops being a hunch, because every indicator carries the log line that flagged it, from a sensor with no legitimate traffic, so "this host brute-forced SSH on 14 August" is a fact rather than a reputation claim.

In your SIEM

The scored list loads as a lookup and joins against what you already collect. In Splunk that is one command against firewall, VPN or authentication events:

index=firewall action=allowed
| lookup ctif_blocklist ip AS src_ip OUTPUT hostility_score, country, asn
| where hostility_score >= 60
| stats count sum(bytes) AS bytes BY src_ip, hostility_score, asn
| sort - hostility_score

The Splunk guide has the cron entry and the transforms.conf stanza. MISP and OpenCTI ingest the same CSV if your intelligence lives in a platform rather than the SIEM.

False positives are a design problem, not a support ticket

The two things a SOC must never block are a CDN edge and a research scanner, and both are noisy enough to float to the top of any volume-based ranking. CTIF caps them at 20 rather than deleting them, so you can still see them and still never act on them. Confirmed false positives are hidden rather than erased, so a mistake stays auditable. The scoring weights are published in full on the methodology page precisely so you can argue with them.

What it is not

It is not a detection platform and it will not replace your SIEM. It is IPv4 and IP-centric: no hashes, no malware families, no passive DNS. Coverage is what our own sensors saw, which is real but finite, so absence from the feed is not evidence of safety. If you need a feed to be right about everything, this is the wrong feed. If you need the addresses that are demonstrably attacking exposed services to be ranked and explained, that is exactly what it does.

Evaluating it properly

Run it against a real week. Activate the 7-day trial, which gives a working API key, every sensor, STIX 2.1 and the blocklist at 1,000 requests a day, join it to your own logs, and count how many of the previous week's escalations it would have ranked first. Nothing to sign, no card. From there SMB is 2,000 requests a day and SOC is 10,000.