The end of IOC fatigue: why CISOs need to think in campaigns, not emails

Jan de Vries · 2026-07-30

### The end of IOC fatigue: why CISOs need to think in campaigns, not emails If you're a CISO, you know the drill. Your inbox floods with alerts, each one screaming for attention. You chase down indicators of compromise (IOCs) one by one, hoping to piece together the bigger picture. But here's the thing: that approach is exhausting, and it's not working. Cofense, a leader in phishing defense, has a message for security teams: stop thinking in emails and start thinking in campaigns. It's a shift that could change how you detect threats, respond to incidents, and keep your analysts from burning out. ### Why single-email analysis is failing you Let's be honest. When you analyze phishing emails in isolation, you're missing the forest for the trees. Each email looks like a random event, a lone wolf. But attackers don't operate that way. They launch coordinated campaigns, blasting hundreds or thousands of similar messages across your organization. When you focus on IOCs alone, you're stuck in a reactive loop. You block one sender, and ten more pop up. You quarantine one attachment, and another variant slips through. It's a game of whack-a-mole, and the mole keeps winning. That's the IOC fatigue we're talking about. Your analysts spend hours on false positives, chasing dead ends, and manually correlating data. The result? Slower response times, missed threats, and a team that's mentally drained. ### The campaign-based approach: a smarter way Here's the good news. You can flip the script. Instead of asking "what does this email do?", ask "what is this campaign trying to achieve?" That simple reframe changes everything. Campaign-based detection groups phishing emails by shared characteristics: sender patterns, subject lines, payloads, and infrastructure. It lets you see the whole attack wave, not just one drop in the ocean. - **Better visibility**: You spot trends across your entire environment, not isolated incidents. - **Faster response**: When you identify a campaign, you can neutralize all related emails at once, not one by one. - **Reduced analyst fatigue**: Your team spends less time on repetitive tasks and more time on real threats. Think of it like fighting a wildfire. If you only douse individual sparks, the fire keeps spreading. But if you spot the firebreak, you can stop it in its tracks. Campaigns are that firebreak for phishing. ### What this means for your security operations Implementing campaign-based thinking isn't just a technical tweak. It's a cultural shift. It requires your team to collaborate differently, to share context, and to prioritize patterns over pixels. Here's what you can expect when you make the switch: 1. **Quicker triage**: Analysts can classify and escalate threats based on campaign severity, not just individual email scores. 2. **Smarter automation**: You can automate responses for entire campaigns, freeing up human brainpower for complex investigations. 3. **Better reporting**: Executives get a clearer picture of risk when you talk about campaigns, not just raw email counts. And let's not forget the human side. A less fatigued analyst is a sharper analyst. When your team isn't drowning in noise, they can actually think, connect dots, and catch the attacks that matter. ### A practical first step If you're ready to move beyond IOC fatigue, start by reviewing your current phishing analysis workflow. Are you correlating emails by campaign? Do you have tools that cluster similar threats? If not, that's your gap. You don't need to overhaul your entire stack overnight. But you do need to shift your mindset. Ask your team one question in your next meeting: "Are we fighting emails or campaigns?" The answer might surprise you. In the end, phishing isn't going anywhere. But you can change how you fight it. Campaign-based detection isn't just a nice-to-have; it's a survival skill for modern security teams. So take a breath, step back, and look at the bigger picture. Your analysts will thank you. *This article was originally published in The European Magazine.*