The core response framework

Based on real-world incident patterns, here is the core framework security teams should follow:

• Revoke access immediately: disable affected accounts, force logouts, and invalidate session tokens across internal systems and cloud platforms.

• Investigate potential misuse: review logs for suspicious logins, lateral movement, or data access.

• Clean the infected device: scan with EDR tools or reimage the machine to eliminate persistence.

• Reset credentials: treat all passwords and session tokens as compromised.

• Strengthen long-term defenses: improve visibility, reduce reliance on unmanaged devices, and close detection gaps.

Why speed matters more than completeness

If you suspect an infostealer is active in your environment, immediate response is critical. These infections often go undetected by traditional tools while silently leaking credentials, session tokens, and business data. Attackers can act within minutes of a log being published on a criminal marketplace, so revoking access first and investigating in parallel matters more than having a perfect, fully-documented process before you start.

Getting ahead of the next incident

A one-time response gets you through this incident. Continuous monitoring of criminal marketplaces is what tells you about the next one before it escalates, since new infostealer infections happen on an ongoing basis, not as a single event.

Passguard monitors criminal marketplaces and Telegram channels continuously and alerts your team the moment stolen sessions linked to your organization appear, so your response can start before attackers act.