A CISO’s guide to monitoring the dark web

Most security leaders know the dark web exists, but many still view it as the internet’s seedy underbelly — useful for criminals who want to make illegal transactions, but not a source of information for those who walk the straight and narrow. That’s a mistake.

Cybercriminal networks responsible for ransomware attacks and credential leaks do business on the dark web, and dark web sites offer vital context for cybersecurity pros. Moreover, the dark web can provide early indicators that your systems have been compromised, if you know where to look.

We spoke to security experts to learn how to monitor dark web activity, what to watch for, and how to turn what you find into real-world defensive action.

Why you need to monitor the dark web

Information on the dark web can be a real-time early warning system, offering you first indications that your organization has been breached — or is next on the list.

“Finding data on the dark web may mean that a breach was missed and the organization will have to respond accordingly,” says Nick Carroll, cyber incident response manager at Nightwing. That discovery should set off a chain of actions: “Verify the data’s authenticity, assess the scope of the exposure,” he says. “If the leak stems from an ongoing breach, immediate containment is vital.” Carroll also advises organizations to preserve evidence, notify affected parties as required by law, and be ready for possible extortion attempts.

Continuous monitoring of the dark web is essential, Carroll adds, because “the dark web moves quickly,” and it’s not just a matter of detecting past breaches. “We also track ransomware group operations regularly and dark web postings around leaked victim data. This helps inform our threat hunters on which ransomware actors are focused on which industry verticals.”

That kind of threat visibility can be the key to stopping an attack before it unfolds. “Look for stealer logs, brand mentions, and initial access brokers offering RDP or VPN access,” says Sıla Özeren, a security research engineer at Picus Security. “These signals often emerge well before ransomware deployment. We have seen organizations intercept attacks in progress simply because they knew they were in the crosshairs.”

Ozeren advises CISOs to “use this knowledge to build and refine your incident response playbooks and conduct adversarial simulations to test how well your defenses hold up against real-world attack behaviors.”

Dark web monitoring can also provide strategic intelligence even when it doesn’t uncover direct mentions of your organization. For instance, understanding which groups are targeting your industry or region helps security teams allocate resources more effectively.

“Knowing which groups are active can help prioritize patching and detection efforts,” says James Wood, principal consultant at global technology research firm ISG. Subscribe to threat intelligence feeds and participate in sector-specific information sharing and analysis centers (ISACs) to stay ahead of ransomware trends and relevant indicators of compromise, he advises.

Tony Velleca, CEO of Cyberproof, also emphasizes the value of ISACs and Computer Emergency Response Teams (CERTs), which “routinely release industry-specific ransomware incident data and warnings.”

Velleca adds that security teams should “track emerging vulnerabilities in software commonly used by your sector,” because ransomware groups pounce quickly. Use threat intelligence feeds “that map exploited vulnerabilities to active ransomware campaigns in particular industries,” he advises.

That sector-specific targeting is also visible in ransomware groups’ recruitment patterns. “If an [affiliate recruitment] ad like ‘Looking for SaaS or CRM partners’ appears, it’s a direct signal that your industry is being targeted,” says Aleksandr Adamenko, co-founder of Winday.co, noting that such indicators can help CISOs connect the dots between dark web activity and emerging threats to their business.

Even when there’s no immediate danger, dark web monitoring can strengthen defenses by providing insight into how attackers operate. “Be aware of the tactics, techniques, and procedures used in cyberattacks, and stay current with real-world attack scenarios,” says Stacey Cameron, CISO at anti-ransomware company Halcyon. She cites examples such as “discussion of unpatched or zero-day vulnerabilities, often tied to specific operating systems, VPNs, or remote access tools,” and the sale of “harvested credentials, both human and non-human, especially for cloud and SaaS platforms.”

How to monitor the dark web

Getting access to all this information is easier said than done — and many may find it intimidating. At the most basic level, there are free tools that offer entry-level visibility. “‘Have I Been Pwned,’ for example, is a free and reliable service for checking if an email address was involved in a known breach,” says Crystal Morin, cybersecurity strategist at Sysdig. “It also offers paid tiers of enterprise monitoring for all email addresses associated with a corporate domain.”

More advanced capabilities, however, require persistent access to hard-to-reach corners of the dark web. “Truly effective dark web monitoring goes much deeper,” Morin says. “It requires tracking several forums, Telegram channels, breach dump sites, and so on — some of which require vetting to join and/or are language-specific. That’s why many organizations rely on threat intelligence platforms such as Flashpoint or Recorded Future.”

ISG’s Wood notes that these providers can “continuously scan underground forums, marketplaces, and breach dumps to alert you when your company’s data appears.”

Among commercial solutions, two names came up repeatedly: SpyCloud and DarkOwl. According to Winday.co’s Adamenko, “SpyCloud is an automated protection against leaks and stolen credentials. It is a SaaS platform that has the ability to automatically monitor the dark web, forums, dumps, private databases to find leaked credentials, cookies, sessions, tokens, etc.” It integrates with existing security operations center (SOC) solutions and provides real-time alerts if corporate credentials surface on the black market.

DarkOwl, by contrast, focuses more on analytics and strategic insights. “They have their own search engine that works like a ‘Google for the dark web’ — with the ability to create contextual queries, filter by leak type, location, time of appearance, etc.,” says Adamenko. He characterizes SpyCloud as better-suited for “operational account protection, phishing prevention, and partner verification,” while DarkOwl is aimed at compliance teams, threat intelligence analysts, and others building an early warning system.

Regardless of the platform, expertise is essential. “If there is no experienced security analyst in the team, involve external expertise at the integration stage,” Adamenko says. “Otherwise, you risk simply collecting alerts without knowing how to interpret or act on them.”

For an in-depth look at more offerings in this space, check out “12 dark web monitoring tools“ from CSO’s Tim Ferrill.

For organizations looking for more proactive threat detection, deception technologies such as honeypots and canary tokens offer powerful options.

IEEE Senior Member Shaila Rana suggested that companies “set up honeypot email addresses or fake info and employee credentials that only exist to trigger alerts if they appear in breach databases.” Another tactic is to “create ‘canary tokens’ that are fake but realistic documents with embedded tracking that could ping if accessed.” These lures can be particularly useful in detecting insider threats or spotting compromised internal assets circulating online.

Adamenko also endorses using honeypots, but warns of the risks if not implemented properly: “A honeypot is a very effective tool, but mistakes in its configuration can create more risks than benefits.” He suggests that companies without experienced internal security teams “turn to a specialized contractor who already has proven configurations, response logic, and infrastructure.”

However, organizations with mature security operations can go further. “If the company already has an internal devsecops team or its own SOC, then it is possible and advisable to implement the honeypot independently,” Adamenko says. With proper integration into SIEM or XDR tools, honeypots can act as early indicators of targeted activity.

Security teams can also enhance visibility by joining vetted communities of dark web analysts. Adamenko pointed to “private Telegram channels and feeds, where information about potential threats, hacks, or mentions of your brand or infrastructure appears before public sources.”

On whatever level your organization engages with the dark web, be sure to use strong operational security practices. Ed Currie, associate managing director of Cyber Threat Intelligence at Kroll, suggests “using trusted Tor browsers, VPNs, and dedicated devices, and disabling scripts that could expose identity.” He emphasized that accessing the dark web is legal and even necessary for security professionals, “but it must be approached with a strategic mindset focused on intelligence gathering rather than fear.”

What to look for on the dark web

Imagine you have your dark web monitoring tools up and running. What should your team look for? The first step is to perform the dark web equivalent of Googling yourself.

“Modern dark web monitoring platforms continuously scan dark web forums, marketplaces, and paste sites for company-specific information,” says Cyberproof’s Velleca. These tools allow you to “search for company domains, executive emails, and tailored terms, like a CEO’s name or even partial Social Security numbers.”  These details may seem minor, but when combined with other compromised data, they can be used to engineer devastating social or financial attacks.

If you’re looking for broader threats against your organization, pay close attention to what initial access brokers (IABs) are offering for sale on the dark web. “We regularly monitor IAB sales offerings to see if there’s any alignment between what’s being posted and our clients’ risk profiles,” says Nightwing’s Carroll. “Our analysts track posts from known IABs offering things like VPN/RDP access, admin credentials, or vulnerabilities in specific companies’ infrastructure.”

Winday.co’s Adamenko adds practical advice: “Monitor marketplaces and forums that sell access to companies. Set up monitoring for mentions of your domain, IP addresses, or common usernames in sections like ‘RDP access,’ ‘VPN for sale,’ etc. Brokers often explicitly state which companies they have initial access to.”

The scope of effective dark web monitoring should go beyond your company alone. Third-party risk is a major — and growing — concern, says Stephen Boyce, founder of The Cyber Doctor. “Many dark web actors target smaller suppliers, managed service providers, SaaS vendors, or even law firms with access to your systems or data,” he says. He advises monitoring forums and marketplaces not just for your own company’s name, but for “mentions of your key vendors and technology stack — especially anything with privileged access, like SSO providers, CRM systems, or cloud infrastructure.

“If someone is offering access to one of your partners,” Boyce warns, “that may be a precursor to an attack on you via lateral movement. Proactively identifying this threat allows you to contact the vendor, assess your exposure, and isolate critical systems before an attacker gets in through the side door.”

Turning dark web intelligence into action

Gathering intelligence from the dark web is useful only if you know what to do with it. The most effective security programs don’t treat dark web monitoring as a siloed activity; they bake it directly into their detection and response workflows.

“Companies must integrate [what they find on the dark web] into their internal monitoring,” said Ariel Parnes, COO of incident response firm Mitiga. That means “automatically cross-referencing indicators against authentication logs, identity changes, and anomalous behavior across platforms such as AWS, Azure, Okta, and M365, to name a few.” 

When something suspicious surfaces, like a stolen session token or exposed admin credential, Parnes stresses the need for rapid action: “They must trigger immediate investigation workflows, revoking access, re-enrolling MFA, or isolating affected services.”

ISG’s Wood also urges organizations to link external intelligence to their internal processes. “Develop an incident response playbook,” he says, with plans laid out so you can “be ready to act immediately if your data appears for sale or extortion on the dark web.”

That readiness also includes knowing what signs to look for. We’ve already noted that IABs are often shopping around VPN and RDP access to target companies; if you know your organization is being targeted by IABs, you should be on the lookout for exactly these kinds of attacks.

“When we see patterns like unusual remote access activity increase, spikes in VPN or RDP usage, or credentials being reused across systems, these are often not random anomalies,” Wood says. “These patterns are a signature of cybercriminal ‘supply chain’ behavior, not just individual hackers.”

By mapping external signals — dark web listings, threat actor chatter, credential leaks — to real-time telemetry from your environment, security teams can detect attacks not just when they happen, but as they’re being planned. In the end, dark web monitoring isn’t just about watching in the shadows. It helps you shine a light within your own perimeter, and spot things that don’t belong.