Live Threat Pulse: 2,847 threats detected in last 24h

menu_book Concept

Account Takeover (ATO)

Also known as: ATO, Account compromise

Account takeover (ATO) is when an attacker gains unauthorized control of a legitimate user account, typically using stolen credentials or session cookies. ATO enables fraud, data theft, and lateral movement, and infostealer-sourced data is a major driver of it.

What is account takeover?

Account takeover occurs when a malicious actor logs into and controls an account that belongs to someone else. They may change recovery details to lock out the real owner, drain funds, exfiltrate data, or use the account as a foothold for further attacks.

How attackers achieve ATO

ATO is commonly achieved with compromised credentials from infostealer logs or breaches, with stolen session cookies that bypass MFA, through credential stuffing, and via phishing. Infostealers are especially effective because they provide both credentials and the cookies needed to sidestep additional verification.

How VantaPrism Tracks Account Takeover (ATO)

VantaPrism reduces ATO risk by detecting compromised credentials and stolen session cookies for an organisation's users early, so accounts can be secured before takeover occurs.

Check Your Exposure arrow_forward

Frequently Asked Questions

How do attackers commit account takeover with cookies?

expand_more
A stolen, still-valid session cookie can be imported into an attacker's browser to resume an authenticated session, bypassing the password and MFA prompts entirely.

What are signs of account takeover?

expand_more
Logins from unfamiliar locations or devices, changed recovery email or phone, unexpected MFA prompts, and unauthorized transactions or messages.
← All Glossary Terms Last reviewed: June 2026