There are ways to OTP bypass (One Time Password). We will discuss them below.
Response Manipulation (OTP bypass)
If the OTP is checked on the client side, we can use this technique. We have to use a Web Proxy like Burp Suite for capturing and modifying the response. Steps:-
1. On OTP verification, enter any passcode.
2. Intercept the request through proxy.
3. Modify the response to be accepted.
Note: For using this technique, you should know the HTTP code and message for successful OTP verification.
Direct Request/Forceful Browsing
Directly go to the website that comes after OTP validation. Then there is a need for 2FA itself. This is possible in when the application lacks authorization checks or doesn’t properly implement them. For using this method, the user should know the URL that comes after the verification.
CSRF & Clickjacking to Disable MFA
Assume that the application has functionality for authenticated users to disable the MFA and there is no password/authentication verification on it. Assuming that if the application is also vulnerable to Cross-Site Request Forgery (CSRF) or Clickjacking, the attacker can utilize these attacks to trick victim users to turn off their MFA and remove the blocker & use the compromised credentials to access the victim account.
Bypassing 2FA using blank code, add a string and null code
The application doesn’t check for null or empty code in the 2FA authentication process. Sometimes the 2FA can be bypassed by sending a blank code or null code.
As we navigate the intricacies of digital security, the concept of ‘bypass OTP‘ emerges as a focal point, revealing a dynamic interplay between safeguarding measures and potential vulnerabilities
{OTP:’123456′} => {OTP:”}
{OTP:’123456′} => {OTP:’null’}
{“otp”:”123456″} = 403 + wrong otp
{“otp”: true} = 200 + rest token
OTP Code Reusability
When the application doesn’t invalidate a previously used OTP and the expiration time-frame is considerable say 1 day. It can be abused by an attacker to brute-force or guess for a valid (even complex) OTP bypass the restriction. To check if this issue is present, the following steps can be carried out:
- The attacker requests an OTP and uses it.
- Now, in the next iteration, the attacker uses the same old OTP and if the OTP is accepted as valid, the issue is present.
Code Leakage in Response
Sometimes the application leaks the OTP somewhere in the response body while initiating a request for OTP. It is always a good idea to read the response body and understand if there is any possible leakage that can lead to bypassing the MFA.
Missing Brute-Force Protection on bypass OTP Validation
Attackers sometimes opt for a brute force approach depending on the age of the equipment being used by the target. For example, some legacy keyfobs are only four digits long and thus easier to crack (longer OTP codes increase the difficulty because there are more permutations to decipher).
The obstacle for hackers is that OTPs are only valid for a short time, usually just a few seconds to minutes. So, there are a limited number of codes to try before it changes. When 2FA is implemented correctly, the 2FA authentication server prevents this type of attack by only allowing a small number of incorrect OTP codes per user. This is possible when there is no rate limiter in the application.
Bypassing 2FA with Session Cookie or Man-in-the-middle
Cookie stealing, otherwise known as session hijacking, is stealing the user’s session cookie. When users log into a site, they do not need their password every time.
A cookie contains the user’s information, keeps the user authenticated, and tracks their session activity. The session cookie stays in the browser until the user logs out, and closing the window doesn’t log the user out.
So, an attacker can use the cookie to his advantage. Once the hacker acquires the session cookie, he can bypass the two-factor authentication. Attackers know many hijacking methods, like session sniffing, session fixation, cross-site scripting, and malware attacks.
Also, Evilginx is a popular framework that hackers use for man-in-the-middle attacks. With Evilginx, the attacker sends a phishing link to the user, which takes the user to a proxy login page. When the user logs into his account using 2FA, Evilginx captures his login credentials and the authentication code.
Because the OTP expires after using it and is only valid for a short time, there’s no need to capture the authentication code. Instead, the hacker has the user’s session cookies, which he uses to log in and OTP bypass the two-factor authentication.
Password reset
One of the easiest and, therefore, most common ways to bypass two-factor authentication is by simply utilizing the password reset function of websites and applications.
Although every login function should require the second authentication factor after two-factor authentication is enabled, one of them is often forgotten. A surprising number of platforms allow users to access an account after obtaining a password reset token without additional verification. Obviously, such a blatant security hole makes the job of attackers significantly easier.
Duplicate-Generator
Akin to many other 2FA bypass attacks, the Duplicate-Generator is also intended to exploit the security holes in this authentication method. Or, more specifically, the flaws of the one-time-password (OTP).
Interestingly, many platforms seem to rely on number generators to create the security key used as the second authentication factor. These OTP bypass generators typically begin with a randomly chosen seed value, which is used to produce the first number in the verification code. If this seed and the algorithm are learned, the attacker can produce a duplicate of the victim’s generator that will display the identical set of numbers – and thus, find out the OTP.
Conclusion
In the realm of modern digital security, the exploration of “Top 10 Methods for OTP Bypass” has illuminated a landscape where intricate algorithms and ingenious tactics intersect. From manipulating algorithms to deciphering codes, the journey through these techniques underscores the delicate balance between safeguarding transactions and the potential for vulnerability. As we conclude our exploration, the significance of staying informed about “otp bypass file,” “otp bypass number,” “online otp bypass,” and the broader “bypass otp” concept becomes evident. Armed with this knowledge, individuals and organizations alike are empowered to fortify their digital defenses, ensuring a safer online presence in an increasingly interconnected world.
