Short answer

When evaluating an infostealer monitoring tool, focus on: marketplace coverage, detection of session tokens alongside credentials, actionable context per infection, API access for integration, and data residency. Tools that only check breach databases miss the most dangerous part of the infostealer threat.

Key evaluation criteria

• Marketplace coverage: does the tool monitor the criminal marketplaces where infostealer logs are actually traded? This includes dark web forums, Telegram, and Discord. Not all tools have access to the same sources.

• Session token detection: does it detect stolen session tokens and cookies, or only passwords? Session tokens bypass most MFA methods, this is the highest-risk data in a stealer log.

• Context per detection: when a detection is made, do you get enough context to act? Look for: device information, malware type, infection timeline, and specific sessions compromised.

• Speed of detection: how quickly after a log appears on a marketplace are you alerted? Hours matter, stolen sessions can be used immediately.

• API access: can you integrate alerts into your existing security stack (SIEM, SOAR, ticketing)? Manual dashboard-only tools create operational overhead.

• Data residency: where is the data processed and stored? For European organizations, a provider that operates within the EU may be required.

Red flags

Be cautious of tools that claim to be infostealer monitoring but only check against historical breach databases. Watch for tools that detect compromised sessions but do not provide device context or infection details: without this, your response is limited to blanket password resets. Also ask vendors how they source their data: some providers pay criminals directly for stolen logs, which raises ethical and legal questions. Passguard does not pay criminals for data.