Short answer

Breach monitoring checks whether your credentials appear in known data breaches, historical events where databases were leaked. Infostealer monitoring detects when data from actively infected devices is being sold on criminal marketplaces in real-time. The key difference: breach monitoring is reactive (the breach already happened), while infostealer monitoring catches ongoing, active threats.

Breach monitoring: strengths and limitations

Breach monitoring is valuable for detecting when employee credentials appear in leaked databases. Services like Have I Been Pwned aggregate known breaches and make them searchable. But the core limitation is that this data is historical. The credentials found in breach databases are often years old by the time they are indexed. Forcing a password reset is the standard response, and it works for password-based attacks. But it does nothing for stolen sessions, which are live at the time of infection.

Infostealer monitoring: what it adds

Infostealer monitoring covers the gap that breach monitoring misses. When a device is infected with an infostealer, the stolen data is sold on criminal marketplaces within hours. This data includes session tokens that bypass most MFA methods, a threat that password resets do not mitigate. Only session revocation stops this attack.

Additionally, infostealer monitoring provides device context: which device was infected, what malware was used, and exactly which sessions are compromised. This enables targeted response rather than blanket password resets.

Do you need both

Yes. Breach monitoring covers historical credential exposure. Infostealer monitoring covers active, real-time threats. And beyond that, there are leaks and emerging threats that fall outside both categories. Together, full-spectrum monitoring provides complete visibility into credential and session compromise. Passguard covers both sides: it monitors criminal marketplaces (dark web forums, Telegram, and Discord) for stolen sessions from actively infected devices, and simultaneously tracks breaches, leaks, and emerging threats. One platform, complete visibility.