Infostealer Malware
Also known as: Info-stealer, Information stealer, Stealer malware
Infostealer malware is a category of malicious software designed to silently harvest sensitive data — passwords, session cookies, autofill information, cryptocurrency wallets, and files — from an infected device and exfiltrate it to attackers, who package the results into "stealer logs" for sale or exploitation.
What is infostealer malware?
An infostealer (information stealer) is malware whose primary purpose is data theft rather than persistence or destruction. After infecting a device, it scrapes credentials, browser cookies, autofill and payment data, cryptocurrency wallets, and sometimes documents, then sends that data to a command-and-control server or a Telegram channel.
Most modern infostealers are sold as malware-as-a-service, which has turned credential theft into a high-volume, industrialised criminal economy.
The infostealer supply chain
Infostealers sit at the start of a broader attack supply chain. The data they steal — packaged as stealer logs — is sold or traded across marketplaces and channels. Buyers include initial access brokers, ransomware affiliates, and fraudsters, who use the credentials and cookies to break into corporate networks, take over accounts, and commit financial crime.
Why infostealers are so dangerous
A single infostealer infection can expose a person's entire digital footprint at once, including corporate logins used on a personal device. Stolen session cookies allow attackers to bypass multi-factor authentication, and because logs are resold repeatedly, exposures can remain exploitable for months or years.
VantaPrism is built specifically around infostealer intelligence: it monitors the channels where stealer logs are distributed, ingests and parses them in near real time, and lets organisations discover whether their credentials, cookies, or assets appear in the data before attackers act on it.
Check Your Exposure arrow_forwardFrequently Asked Questions
What is the difference between an infostealer and other malware?
How do infostealers infect a device?
Can infostealers bypass multi-factor authentication?
Related Terms
A stealer log is the package of data exfiltrated from a single device by infostealer malware. It typically contains s…
RedLine Stealer is an information-stealing malware (infostealer) sold as malware-as-a-service that harvests saved bro…
Lumma Stealer (LummaC2) is a malware-as-a-service infostealer that steals browser credentials, cookies, cryptocurrenc…
Compromised credentials are usernames and passwords that have been exposed to unauthorized parties — frequently throu…
Cookie theft is the stealing of browser cookies — especially authenticated session cookies — so attackers can imperso…
Malware-as-a-service (MaaS) is a criminal business model in which malware authors rent or sell their software, infras…
An initial access broker (IAB) is a cybercriminal who sells access to compromised networks and accounts to other atta…