Why staying hidden is the business model

Infostealers are purpose-built to remain undetected for as long as possible. The longer a victim is unaware of the infection, the longer the stolen credentials remain valuable. Once a breach is discovered, passwords are reset, tokens are revoked, and access is lost. That is why infostealers operate quietly: it preserves the resale value of logs in the criminal marketplace. Delayed detection is not a side effect, it is the business model.

Their behavior is short-lived and typically does not rely on persistence, especially in early stages, and often happens outside of the organization’s security perimeter.

Why traditional tools miss them

Most AV and EDR systems fail to catch infostealers because of three factors:

• They execute briefly and in-memory: leaving no trace for behavioral analysis or sandboxing.

• They don’t require persistence to be effective: though some establish footholds later via droppers, autostarts, or scheduled tasks.

• They operate outside managed environments: many infections occur on personal, BYOD, or unmanaged devices that are not covered by endpoint protection.

Even advanced EDR tools struggle to detect infostealers when the device is not enrolled in management or when telemetry is unavailable. Many stealers use techniques documented in MITRE ATT\&CK T1555.003, extracting credentials from local storage or password managers without triggering alerts.

What actually closes the gap

Because most infections happen on endpoints the organization does not control, traditional security tools cannot see them and never raise an alert. Closing this gap requires looking beyond the endpoint entirely, at the criminal marketplaces where stolen sessions surface after the infection has already happened.

Passguard monitors these marketplaces continuously, so you are alerted even when your antivirus or EDR never saw the infection at all.