An
infostealer is malware designed to collect information such as stored credentials, browser session data, files or wallet details. Its exact capabilities depend on the variant. The danger is not limited to a single password: a stolen active session may give access to an account that already passed MFA.
Quick example
Someone runs a fake software installer. It secretly copies saved browser credentials and session material. Resetting just one password may leave other accounts exposed.
What to do
Stop using the suspect device for sensitive sign-ins. Update and run trusted security software, then secure important accounts from a clean device. Review active sessions, saved passwords and recovery settings. If you cannot establish that the device is clean, seek qualified help before restoring sensitive access.
MITRE documents web-session-cookie theft as one possible technique; it is not proof that every malware detection stole your data.
Practical distinction
If a scan names an infostealer, record the detection and time, then review accounts used on that device. You cannot infer the exact stolen data from the malware family name alone.
