Account Takeover: What Is It and How to Fight It

Account takeover (ATO) attacks can devastate individuals and organisations, from personal profiles to enterprise systems. The financial impact alone is huge; for instance, in 2023, global losses caused by ATO fraud exceeded $13 billion.

Yet, the damage doesn’t stop there. Beyond monetary loss, organisations face severe operational disruptions and long-lasting reputational harm, often far costlier than direct theft. With ATO incidents increasing by an estimated 354% year over year, this form of fraud is spreading at an alarming pace.

This guide examines the true risks of account takeovers, the most common attack strategies, and the defensive measures that can help secure your systems for good.

****What Is Account Takeover and Why Is It Dangerous?****

Account takeover is a cybercrime in which an unauthorised actor gains full or partial control of a legitimate user’s account. Unlike brute-force hacks, ATO relies heavily on deceit and the exploitation of weak points in systems and user behaviour to remain undetected.

****Why ATO Shouldn’t Be Underestimated****

It’s easy to dismiss ATO as a niche cybersecurity issue, but it has far-reaching implications across multiple fronts.

1. One breach leads to another

Attackers rarely stop after compromising a single account. Access to one login, such as an email, can reveal sensitive information that opens the door to broader internal systems.

2. Stolen accounts are a commodity

Compromised credentials are often sold on underground markets, fueling an entire ecosystem of financial fraud, money laundering, and scams executed under the guise of legitimate accounts.

3. A tool for larger crimes

ATO frequently plays a role in broader cyber schemes like ransomware, espionage, or misinformation campaigns. For instance, if a senior executive’s account is compromised, it could be used to spread phishing emails or leak proprietary data.

4. Loss of trust

Reputation is hard-earned and easily damaged. Each successful account compromise erodes the confidence that users and partners place in your systems, something that can take years to rebuild.

****Who Is Most Exposed to Account Takeover?****

Some industries and account types attract attackers more than others. Cybercriminals tend to focus on targets that combine high potential profit with relatively weak defences.

****Financial Institutions****

Banks, trading platforms, and fintech services are obvious targets due to the direct access they provide to funds.

• Cryptocurrency exchanges: Their irreversible transactions and inconsistent regulations make them particularly vulnerable.
• Buy now, pay later services: These fast-growing platforms often have less mature fraud detection systems.

****Retail and E-Commerce****

Online retailers hold massive volumes of user accounts linked to stored payment data. Attackers exploit these to make fake purchases, redeem loyalty points, or resell stolen gift cards.

• Seasonal surges: Attack activity typically spikes during holidays and major sale events.
• Omnichannel risks: Integrating multiple systems (web, app, POS) can introduce new vulnerabilities.

Healthcare Organizations

Patient data, such as social security numbers and insurance details, is extremely valuable on the dark web.

• Patient portals: Commonly targeted to commit identity or insurance fraud.
• Ransomware infiltration: Stolen credentials can be used to launch ransomware attacks that disrupt patient care.

****Technology and SaaS Providers****

Tech companies, especially SaaS vendors, are lucrative because one breach can compromise multiple customer environments.

• Weak API protection: APIs linking various services can serve as entry points.
• Admin accounts: Their elevated privileges make them especially high-impact targets.

****Educational Institutions****

Universities and schools hold extensive personal, academic, and financial data. Attackers exploit them to:

• Impersonate others during exams
• Access confidential research and IP
• Manipulate tuition or payroll systems
• Commit identity theft using student or staff information

****Common Patterns Among Vulnerable Targets****

Despite industry differences, high-risk systems tend to share these features:

• Large user volumes
• High account value (financial or strategic)
• Outdated or weak authentication methods
• Interconnected systems that increase attack surfaces

****How Attackers Execute Account Takeovers****

Every ATO incident typically unfolds in two stages: information gathering and access exploitation.

****Step 1: Acquiring Sensitive Data****

Attackers collect personal information through various means:

• Data breaches: Massive leaks of usernames, passwords, and personal details feed dark web marketplaces. Hackers often cross-reference different breaches to build complete user profiles or predict password patterns.

• Social engineering: Techniques like vishing (voice phishing), SMiShing (SMS scams), and pretexting manipulate victims into revealing their credentials.

• Data scraping: Using open-source intelligence (OSINT), attackers gather information from public records and social media to craft more convincing phishing schemes.

• Malware: Keyloggers, spyware, and credential-stealing tools such as Emotet or TrickBot silently capture login data over time.

****Step 2: Exploiting Access****

Once armed with credentials, attackers deploy several methods to hijack accounts.

• Credential stuffing: Automated tools test vast combinations of usernames and passwords, taking advantage of reused credentials.
• Password spraying: Attackers try a single common password across multiple accounts.
• Session hijacking: By intercepting active session tokens via man-in-the-middle attacks or malware, criminals gain temporary control over accounts.
• SIM swapping: Fraudsters trick telecom providers into transferring a victim’s phone number, allowing them to intercept SMS-based 2FA codes.

****How to Defend Against Account Takeover****

While ATO attacks are sophisticated, organisations can significantly reduce their risk through layered defence mechanisms.

****Multi-Factor Authentication (MFA)****

MFA, also known as two-factor authentication (2FA), adds extra verification layers beyond passwords. Although SMS-based codes are common, they’re susceptible to SIM swapping. More secure alternatives include:

• Hardware security tokens
• Time-based one-time passwords (TOTP) from authentication apps
• Contextual authentication, which evaluates login location, device, and behaviour to decide when to require stronger checks

****Strengthen Password Policies****

Encourage users to create unique, complex passwords and change them regularly without following predictable patterns.

Password managers can help generate and store secure credentials, and account lockout mechanisms should activate after repeated failed login attempts.

****Embrace Zero Trust Architecture****

Under a Zero Trust model, no user or device is automatically trusted, even internal ones.

• Apply the principle of least privilege to limit user access rights.

• Use network microsegmentation to isolate systems and minimise lateral movement.

• Closely monitor mobile access requests and use automated systems to suspend suspicious accounts until verified.

****Integrate Biometric Verification and Liveness Detection****

Biometric authentication verifies a user’s identity by comparing their facial features to stored reference images.

Solutions like Regula Face SDK employ advanced algorithms capable of handling variations in lighting and image quality while detecting attempts to spoof authentication with photos, videos, or masks.

Regula’s liveness detection further enhances security by analysing natural human traits like subtle skin reflections and micro-movements to ensure that a real person is present during the verification process.

****Final Thoughts****

Account takeover fraud is escalating rapidly, targeting not just financial gain but also trust and reputation. Preventing it requires a combination of strong authentication, modern security architecture, and advanced verification tools.

By adopting multi-factor authentication, enforcing strict password hygiene, implementing Zero Trust principles, and integrating biometric technologies, organisations can stay several steps ahead of cybercriminals and safeguard both their systems and their users.