Forget the vendor's "curated" list. They'll point you to a hundred premium feeds and call it a start. You don't need that noise.
As a beginner, your must-haves are the free, high-reputation, and high-volume feeds that give you broad visibility without costing a dime. This gets you a baseline. If you can't handle and tune for these, adding paid feeds is a waste.
Here's the bare minimum stack I'd load on day one:
* **Abuse.ch SSL Blacklist (SSLBL):** C2 IPs and SSL certificates. High signal, low false positives.
* **Abuse.ch URLhaus:** Direct download URLs for malware. One of the most actionable for blocking at the proxy.
* **OTX AlienVault Pulses (Community):** Massive volume. You MUST tag and filter aggressively. Start by following a few reputable contributors, not the whole firehose.
* **CIRCL CVE Feed:** Basic vulnerability intel. Keep it simple.
Critical setup note: Don't just ingest them raw. You need immediate filtering or you'll drown.
Example: For OTX pulses, I create an acceptance rule right at the feed source to only ingest pulses tagged with specific malware families or TTPs I care about. The default feed configs are usually terrible.
The real "must-have" isn't a specific feed. It's the discipline to:
* Start with these free ones.
* Measure their hit rate in your environment.
* Tune the hell out of them before adding a single paid feed.
Otherwise, you're just building a threat intel junk drawer.
-- bb
-- bb
Agree on the feeds, but that "setup note" is the whole game.
> Don't just ingest them raw.
Most SIEMs have zero filtering by default when you add a feed. The default is 'ingest everything'. If you pull in OTX community pulses unfiltered, you'll get thousands of irrelevant IOCs from random users. Your storage costs and alert fatigue will blow up before you learn anything.
You need to filter at the source connector if possible. If your tool can't do that, you have to build the filtering logic yourself right after ingestion. Otherwise you've just deployed a denial-of-wallet attack.
Least privilege is not a suggestion.
Yeah, the filtering point is huge. I'm setting this up for the first time at work, and the default config for our connector was indeed "grab everything." I got a ton of pulses for malware we'd never see in our tech stack.
How do you actually pick those starting tags or TTPs, though? I get the idea, but as a beginner, I'm staring at thousands of tags in OTX. Do you just start with common ones like "Emotet" or "TrickBot" and expand from there?
Learning by breaking
Completely agree on the foundational nature of those specific feeds. The logic of "if you can't handle these, don't add more" is sound.
A point I'd add for anyone coming from a support or operations background: you need to map these feeds directly to your response capability from day one. For instance, URLhaus is highlighted as actionable at the proxy, but if your team lacks the process or permissions to update block lists quickly, its value plummets. Start by asking: for each feed, who is the action-owner in my organization, and what's the procedure? If the answer is "I don't know," that's your first project, before you ingest a single IOC.
Regarding filtering, I'd stress that your starting tags or TTPs should be informed by your actual tech stack. Instead of just common malware names, cross-reference with your asset inventory. If you don't have any systems running, say, a particular ERP software, then pulses tagged for vulnerabilities in that software are pure noise for you. Use your environment to define the filter, not the other way around.
Support is a product, not a department.
Your setup note about filtering is the key, but I think you undersold the storage cost risk, which is where beginners get hit hardest.
The OTX community feed, unfiltered, can generate tens of gigabytes of stale or irrelevant IOC data per day in a SIEM. If you're on a platform that charges by ingested volume, that's a direct, measurable line item on your cloud bill. You're not just drowning in alerts, you're funding a data lake of threat intel you can't use.
Your rule of only ingesting specific TTPs is sound. I'd make the initial tag list brutally small. Start with two or three active adversaries targeting your core industry, then add one more only after you've proven you can operationalize the alerts from the first set. The goal is to control cost and prove value before you ask for more budget.
Right-size or die
Missing the *other* essential free feed: Spamhaus DROP/EDROP lists. They're netblocks from hijacked or hostile ASNs. Low volume, high impact. Block them at your firewall edge.
That "Critical setup note" is the real takeaway. Beginners skip it and then complain their SIEM is useless.
Your rule about OTX contributors is good, but I'd be more specific: Start with the ones run by actual security vendors or research groups, not independent accounts. The quality gap is massive.
slow pipelines make me cranky
Oh, good shout on Spamhaus! I completely missed that one when I was making my list. The low volume part is a huge plus for starting out.
When you say block them at the firewall edge, is that typically a simple upload to something like an AWS Network ACL or a security group, or is it more involved? Just trying to picture the actual setup.
Good question. The key is to avoid tags for specific malware families like "Emotet" entirely at the start, unless they are actively and directly targeting your industry. They're too narrow.
Instead, focus on behavioral TTPs that represent initial access or execution methods relevant to your stack. For a typical corporate environment, I'd begin with these three categories as filters: `phishing`, `malware-dropper`, and `powershell`. These cut across numerous specific campaigns and give you a foundation of suspicious activity to tune from.
Once that's running, you can review the actual alerts you generate and see which specific adversary or malware tags are attached to them. That's your data-driven list for expansion.
null
Agree completely on the behavioral TTP approach over malware-family tags. That's the correct way to build a high-fidelity baseline.
Your three categories are solid, but I'd add one specific, critical tweak for the `powershell` filter: you must immediately exclude all benign administrative scripts or approved tools from the feed's logic, or you'll be buried in false positives from your own IT team's activity. The first step after enabling that filter is to review what's getting caught and building an allow-list. This turns a noisy feed into a useful one.
This method also gives you a concrete dataset to justify further tuning. You can say, "In the first week, we ingested 5000 `phishing` IOCs, but only 12 were relevant to our email domain after filtering. That shows our filter efficiency and validates starting with broad categories."
Show me the numbers, not the roadmap.
This point about the PowerShell filter is exactly where I've seen people's projects stall. The first alert you get is often from a well-known deployment script like a chocolatey install wrapper that's been in your SCCM for years, and the team goes "see, it's all noise" and turns the feed off.
I'd even take it a step further. Before you even enable that feed, go to your log source and pull a week's worth of PowerShell execution events. Just run a quick analysis to see what the most common script names or command-line patterns are from your own IT and dev teams. That gives you a pre-built baseline allow-list. It's a bit of upfront work, but it means your first day with the feed active is already filtered and useful, which builds immediate confidence.
it worked on my machine
That's a great tip, but it misses a critical contractual snag. That week of log analysis you're proposing? It likely counts as data processing under your SIEM/SaaS license. Ingesting that baseline into your analysis tool to build the allow list could blow through your daily volume cap before you've even turned on the feed.
You need to check if your vendor contract has a separate "pre-production" or "development" tier for this exact scenario. If not, you're paying threat intel rates to profile your own IT scripts.
read the fine print
I think you've nailed the absolute starting point, and your list is solid. The only thing I'd clarify is around the "critical setup note" for beginners.
> You need immediate filtering or you'll drown.
This is 100% correct, but I've seen people interpret "immediate" as something they build after turning the feeds on. For a true day-one beginner, the first step should be to ensure their ingestion platform even *supports* that kind of source-side filtering before they subscribe. If it doesn't, they're already signing up for a flood and might need to pick a different foundational feed to start with.
That capability check is the real prerequisite.
—daniel
Spot on about starting with free, high-reputation feeds. That's the only way to build a baseline you can trust before spending a dime.
Your point on filtering the OTX feed at the source is crucial, but I'd add one specific tactical tip: start by subscribing to pulses only from the *official* vendor accounts, like "AlienVault Labs" or "Malwarebytes Threat Intelligence." Avoid the aggregated "community" view entirely at first. The quality is just so much higher, and the volume is manageable right out of the gate. It cuts the noise in half before you even write a single filter rule.
Cheers, Henry
Finally, someone cutting through the marketing. That's a solid starter list.
But telling a beginner to start with "tag and filter aggressively" on OTX is like telling someone to start a fire by rubbing sticks together. They won't. They'll just turn the feed off in a week.
Better advice: skip OTX entirely for the first month. Get the blocking feeds (SSLBL, URLhaus, Spamhaus) running and learn your platform's filtering with just CIRCL. When you can reliably filter out CVEs for software you don't run, then maybe you're ready for the OTX firehose.
-- old school
Good point about vendor-run OTX accounts. I'd even filter further to just the ones offering feeds for your specific tech stack, like cloud or a certain OS. The generic "threat intel" pulses still contain a ton of irrelevant noise.
And that critical setup note can't be overstated. I've seen people skip it, get overwhelmed, and then decide threat intel as a concept is useless. Filtering at ingestion is the only way to make it manageable.
Automate everything.