OTP bots are automated tools used by cybercriminals to trick victims into revealing their one-time passwords (OTPs), which are typically used in two-factor authentication (2FA) processes. These bots often impersonate legitimate companies via phone calls, texts, or emails, guiding victims to input their OTPs on fake prompts or websites.
2FA and OTPs have been hailed as silver bullets for stopping account takeovers (ATOs), but now over 50% of organizations are now facing AI-enabled attacks, and specialized OTP bots are actively exploiting flaws in the 2FA process.
OTP bot use is a growing threat, as they allow attackers to compromise accounts even when strong authentication methods are in place. This has made OTP bots a favored tool in phishing campaigns targeting financial accounts, email services, and enterprise systems.
What are OTP Bots?
OTP bots are automated tools used by cybercriminals to bypass two-factor authentication by intercepting the temporary codes sent to users via SMS, email, or authenticator apps. These bots play a central role in modern phishing and account takeover attacks by helping attackers gain access to protected accounts even after they’ve obtained the username and password.
The typical attack starts when a victim’s login credentials are stolen through phishing or data breaches. When the attacker attempts to log in, the system sends a one-time password to the user’s device as part of the 2FA process. At this point, the OTP bot comes into play, impersonating a legitimate entity by calling, texting, or emailing the victim. These messages are highly convincing, using spoofed caller IDs or brand logos, and urge the user to verify a suspicious login or complete a security check by providing the OTP they just received.
Victims, believing the request is authentic, provide the OTP to the bot, which relays the code to the attacker. This process effectively defeats the 2FA barrier, allowing full account access.
OTP bots are dangerous because they combine automation with social engineering. They require minimal technical skill to operate and are widely available for purchase, complete with user interfaces and scripted messages. Their use has become increasingly common in attacks on bank accounts, email services, crypto wallets, and enterprise systems.
Simply put, as organizations adopt two-factor authentication, attackers adapt. OTP bots now represent one of the most effective ways to circumvent these protections, contributing significantly to the rise in account takeover incidents across industries.
What is an OTP?
A one-time password refers to an account security mechanism that uses an authenticator app to verify users by providing them with a unique, single-use code for account access. This code expires after one use or a set time period, and cannot be used again. Typically, these passwords are delivered via SMS, email, or through multi-factor authentication apps on smartphones and other devices. OTPs are designed to enhance account security by removing the risk of a password being compromised due to leaks or password reuse.
How Cybercriminals Use OTP Bots to Compromise Accounts
Getting the OTP is only the first step in any account takeover attack. Cybercriminals and fraudsters use a cocktail of sophisticated techniques in tandem with OTP bots to breach and take over accounts. Let’s take a look at the most common methods:
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Gathering Target Information
To begin an attack, cybercriminals often focus on collecting personal data through various means, including data breaches, social engineering, or purchasing from dark web markets. Accessing victims’ emails is a priority for hackers, who can use them to create fake messages, intercept OTPs, and log into accounts.
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Credential Acquisition
Attackers obtain login credentials through phishing, keylogging, or by exploiting password reuse across multiple platforms. Up to 65% of people re-use their passwords across a number of accounts, and comprehensive password lists are fairly affordable and easy to obtain on the dark web.
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OTP Bot Deployment
With the right credentials and information in their possession, the hacker now faces one final obstacle: 2FA. To overcome this, they will use AI to set up the appropriate OTP bot based on the target’s authentication method. For example, they might use advanced LLMs to generate convincing phishing messages or deepfake phone calls or configure automated bots tailored to specific authentication methods. These techniques allow for more sophisticated, scalable attacks that can bypass OTP-based two-factor authentication.
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Initiating the Login Process
With the bot prepared, and the credentials acquired, the attacker only needs to begin logging in to start the attack. Using the stolen credentials, they trigger the OTP request on the target platform.
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OTP Interception and Submission
The bot then intercepts the OTP using a specific method (e.g., SMS interception, phishing, or voice call spoofing). The bot then immediately submits the intercepted OTP to the target platform before it expires, ensuring the hacker can complete the login process.
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Account Compromise
Upon successful authentication, the attacker gains full access to the compromised account. Typically, they then alter contact details and change passwords to lock out the rightful owner of the account before carrying out fraudulent transactions.
Types of OTP Bots
OTP bots come in a number of forms, with each designed to target specific vulnerabilities in different authentication systems. Let’s take a look at these varieties and how they function so you can understand how to build effective countermeasures:
- SMS interceptor bots: These bots exploit weak points in mobile networks to intercept SMS messages containing OTPs. The problem here is that mobile networks continue to rely on Signaling System No. 7 (SS7) protocol, a standard with highly-publicized vulnerabilities that have never been patched. By exploiting outdated security protocols in mobile networks and the lack of encryption in SMS transmissions, these bots are able to extract the OTP and send it to the attacker, often in seconds.
- Phishing bots: These are forms of malicious software (malware) that automate the process of phishing attacks by sending out large volumes of phishing emails or messages with the goal of deceiving recipients into divulging sensitive information like passwords, credit card numbers, or personal data.
- Voice call bots: These bots use automated voice calls to impersonate legitimate services and collect OTPs from unsuspecting users. As AI has advanced, automated phishing voice calls have become increasingly convincing and difficult to detect. The voice call will usually attempt to impersonate a bank or service provider that “needs the OTP for security purposes.”
- Social engineering bots: Automated systems can also use psychological manipulation tactics and generative AI to trick users into revealing their OTPs. One particularly insidious form of this is MFA Bombing, or MFA Spamming, a social engineering cyberattack that uses 2FA against itself by repeatedly overwhelming the user with authentication requests. Eventually, the user is requested to provide authentication via another means in order to stop the notifications and “fix” the problem. This other means involves the user unknowingly sending their OTP directly to the hacker.
- SIM swapping bots: These bots automate requesting SIM card transfers to gain control of a victim’s phone number and intercept OTPs. In an attack like this, the victim’s carrier is tricked into switching the user’s phone number to a SIM card in the possession of cybercriminals. This causes all calls and SMS messages to be sent to hackers instead of the owner of the account.
OTP Bots are Easy to Access
OTP bots have become alarmingly easy to obtain, fueling their widespread use in cybercrime. Services offering these bots are commonly sold on underground forums and messaging platforms like Telegram. Pricing varies depending on the features and support offered, ranging from as little as $40 to $100 per week, or up to $4,000 for lifetime access. These tools often include user-friendly dashboards, customizable scripts, and step-by-step guides, making them accessible even to low-skill attackers.
Telegram has become a central marketplace for these services. In dedicated chat rooms, cybercriminals openly advertise OTP bot packages designed to target specific industries, including social media platforms, fintech apps, and cryptocurrency wallets. These communities not only facilitate sales but also provide technical support, updates, and even customer service for users of the bots.
Because of their low cost and ease of use, OTP bots can be deployed at scale. Attackers can launch widespread campaigns targeting thousands of users with little overhead. This scalability significantly increases the risk for businesses and individuals, making OTP bot attacks a growing threat across multiple sectors.
What is Two-Factor Authentication (2FA)?
Two-factor authentication (2FA) is a security method that requires users to provide two different authentication forms to verify their identity. Considered a form of multi-factor authentication (MFA), 2FA comes in a few different forms, including:
- Fingerprint recognition
- SMS codes
- Email codes
- Software tokens
- Hardware tokens
- Authenticator apps
- Phone calls
By requiring multiple forms of authentication, 2FA makes it significantly harder for hackers to break into accounts. Even if a cybercriminal compromised the account’s password, they would also need the other form of authentication. In a world where 29% of people have experienced at least one account takeover attack, this additional layer of security is increasingly recommended to protect online accounts. However, 2FA now has a weakness: OTP bots.
The Vulnerability of 2FA to OTP Bot Attacks
2FA is one of the most widely used security measures to prevent account takeovers, and for good reason. Requiring 2 forms of authentication does, in fact, effectively mitigate the risks of cyberattacks. However, it is not immune to sophisticated attacks. As 2FA’s popularity has increased, criminals and hackers have redoubled their efforts to find new ways to break through its defenses. They have exposed a major flaw within the armor of 2FA; this digital security measure relies on a single point of failure. If the attacker can obtain the OTP, they can use the code to take over the account.
The Use of OTP Bots is on the Rise
OTP bot attacks are growing rapidly, both in frequency and sophistication. Tools like JokerOTP and BloodOTPbot have been widely used in account takeover campaigns, particularly targeting banking and fintech platforms. According to threat intelligence reports, mentions of OTP bots on dark web forums surged by 31% between 2023 and 2024, reflecting increased demand and usage.
Financial losses linked to OTP bot-enabled attacks are also rising. One report from CloudSEK highlighted that such tools have contributed to over $10 million in fraud losses. Much of this growth is fueled by how easily these bots can be acquired, with full packages sold for a few hundred to a few thousand dollars.
As these tools become more accessible, businesses face growing risks from scalable, real-time social engineering attacks that bypass traditional 2FA protections.
How Sift Prevents ATOs
Whenever a security measure becomes commonplace, cybercriminals will find a way to get around it. This is why it’s so crucial to build a security infrastructure that’s dynamic and capable of responding to new threats in real time. Compared to what came before, 2FA was a great solution, but it’s not perfect. With stolen credentials readily available on the dark web, this “silver bullet” is relatively easy to circumvent due to its single point of failure. To stay ahead of these evolving threats, it’s high time for organizations to embrace AI-powered security measures like Sift’s account takeover solutions.
Sift’s cutting-edge, AI-driven platform enables you to combat ATOs and transform your risk management into a revenue generation center. Embrace the next generation of digital security with these powerful features:
- AI-powered risk assessment: Uses advanced AI/ML algorithms to detect fraud and prevent attacks.
- User behavior analysis: Identifies suspicious patterns that may indicate account takeovers.
- Adaptive authentication: Implements dynamic security measures based on risk level.
- Cross-platform protection: Secures various channels, including web, mobile, and API interfaces.
- Fraud network insights: Uses data from a global network to stay ahead of emerging threats.
- Real-time reporting: Provides actionable insights for quick response to potential attacks.
- Smooth integration: Easily incorporates into existing systems without disrupting user experience.
- Continuous learning: Evolves to address new account takeover tactics as they emerge.
For an example of what these features can do for a business in the real world, let’s look to Rently.
The global property tech company was facing a major problem with account takeover attacks and fraudulent activities were threatening the integrity of their platform. By implementing Sift’s account takeover solution, Rently automated fraud prevention, reducing ATO incidents by 65%, and eliminating six hours of manual review daily.
Learn more about the power of Sift’s AI-powered fraud detection to secure your business against ATO attacks by getting a free demo.
Explore Sift’s ATO Solutions
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