Latest Security Threat – Bypassing 2FA With Cookies!

If you have two-factor authentication (2FA) enabled on your account, you can’t be compromised, right? Well, not exactly. As technology advances, so do the attackers. Phishing attacks have become more sophisticated, and attackers are finding ways to bypass 2FA. The reason why is because of the delicious cookies stored in your browser. Session cookies are a way to show the server that the user has already authenticated, including passing the 2FA challenge. Your browser can use these cookies until they expire. Once the cookie has expired, you will be asked to re-authenticate.

It depends on the application, but some may have stronger restrictions than others. These include:

  • A single-use cookie.
  • Restricted by IP, device, or some sort of fingerprint.
  • Linked to another element which validates the cookie (Anti-Spoofing).

This isn’t the case for all applications, and this is what attackers are exploiting. Services like Outlook, Gmail, and social networking platforms all allow the cookie to be reused. The attacker just needs a way of extracting them.

How Cookies Work

Cookies are small pieces of data stored on the user’s device by their web browser. They are used to remember information about the user, such as login status, preferences, and activity. When you log into a website, a session cookie is created to indicate that you have been authenticated. This cookie is sent with every subsequent request to the server to prove your identity.

There are a handful of tools that simplifies the process of managing cookies out there. While you can view cookies using your browser’s developer tools, extracting them can be cumbersome and error-prone. Cookie editors make these tasks easy to export and import cookies across different browsers or devices. (There are plenty of legitimate uses for these tools as well)

Anyone can log into a web service on one browser, export the session cookie, and then import it into another browser to replicate the logged-in state. This demonstrates how cookies, once exported, can be used to authenticate sessions across different browsers or devices, depending on the application.

How Attackers Exploit Cookies

Attackers are now exploiting this technique. You may be thinking, how are they going to get access to my device though? The answer is they are not trying to. Although this could be achieved with some sort of script or device, it’s unlikely. Instead, they want you to come to them.

lf and bypass any IP and device restrictions. The session cookie would record the source as the theives server, not your client.

Protecting Against Cookie Theft

So, what can you do to protect against this type of attack?

Education and Awareness

The simplest way to fight this is through education. Now that attackers are using HTTPS to seem genuine, we really need to check the URL before entering our credentials.

Verify URLs

Always verify the URL of the site you are visiting. Be wary of slight misspellings or unusual domain names.

Use Strong Security Practices

  • Use security solutions: Employ security tools that can detect and block phishing sites.
  • Enable anti-phishing features: Use anti-phishing features in your browser or security software.
  • Monitor for unusual activity: Keep an eye on your accounts for any unusual activity.

Stay Updated

Keep your software and security solutions up to date to protect against the latest threats.

Commonly Asked Questions About Cookies

Can Two-Factor Authentication Be Bypassed?

Yes, two-factor authentication (2FA) can be bypassed. While 2FA adds an extra layer of security by requiring a second form of verification (like a code sent to your phone) in addition to your password, it is not foolproof. Attackers have developed several methods to bypass 2FA, including:

  • Session Hijacking: Using stolen session cookies to gain access to authenticated sessions without needing the 2FA code.
  • Phishing: Creating fake login pages that capture both the user’s credentials and the 2FA code.
  • Man-in-the-Middle (MitM) Attacks: Intercepting the 2FA code as it is transmitted between the user and the server.
  • SIM Swapping: Taking control of the victim’s phone number to receive the 2FA codes sent via SMS.

Can 2FA Be Cracked?

While 2FA significantly enhances security, it is not invincible. It can be “cracked” or bypassed using sophisticated techniques:

  • Social Engineering: Convincing the user to provide the 2FA code through deceptive means.
  • Credential Stuffing: Using stolen credentials from one site to access accounts on another site, combined with intercepted or phished 2FA codes.
  • Brute Force Attacks: In some cases, attackers may attempt to guess the 2FA code if the method of generation is predictable or the time window is long enough.

Can Phishing Bypass 2FA?

Yes, phishing can bypass 2FA. Attackers can set up a phishing site that mimics a legitimate login page. When the user enters their credentials and the 2FA code, the attacker captures this information in real-time and uses it to log in to the legitimate site. Tools like EvilGinx2 are specifically designed to facilitate this kind of attack by acting as a proxy between the victim and the legitimate site, capturing both the password and the 2FA token.

Why Do Hackers Steal Cookies?

Hackers steal cookies because session cookies store authentication information. By obtaining these cookies, attackers can hijack an active session without needing to re-enter the credentials or pass the 2FA challenge. Essentially, a stolen cookie can allow an attacker to impersonate the user and gain unauthorized access to their accounts and data.

Does Clearing Cookies Stop Hackers?

Clearing cookies can help mitigate the risk of cookie theft by invalidating existing session cookies. However, it does not stop hackers who have already stolen cookies from using them. Once a hacker has a valid session cookie, they can use it until it expires or is invalidated by the server. Regularly clearing cookies can help reduce the duration an attacker can use a stolen cookie but is not a complete solution.

What Happens If a Hacker Gets Your Cookies?

If a hacker gets your cookies, they can impersonate you on any website where the cookie is valid. This means they can access your accounts, view private information, perform actions on your behalf, and potentially change account settings or passwords. The extent of the damage depends on the privileges associated with the stolen cookie.

Can Passwords Be Stolen from Cookies?

Passwords themselves are not typically stored in cookies due to security risks. However, session cookies and other authentication tokens can be stolen, which can allow attackers to gain access to accounts without needing the actual password. Once inside, attackers can often change the password to lock the legitimate user out of their account.

What is Cookie Poisoning?

Cookie poisoning, also known as session hijacking or session fixation, involves modifying the contents of a cookie to gain unauthorized information or access. By altering the data stored in a cookie, attackers can potentially manipulate the session to bypass authentication or authorization mechanisms. This can lead to unauthorized actions or access to sensitive data within a web application.

Can Cookies Lead to Identity Theft?

Yes, cookies can lead to identity theft. Session cookies, in particular, store authentication information that can be used to impersonate a user. If attackers steal these cookies, they can access personal and financial information, perform unauthorized transactions, and gather enough data to commit identity theft. This can result in significant financial loss and damage to the victim’s credit and reputation.

What Happens If I Block All Cookies?

Blocking all cookies can significantly enhance privacy and security by preventing websites from storing any data on your device. However, it also means that many websites will not function properly. Essential features, such as logging in, retaining user preferences, and shopping cart functionality, will be disrupted. Users may find it difficult to use websites that rely heavily on cookies for their core functionality.

What Happens If I Reject Cookies?

Rejecting cookies can help protect your privacy by preventing websites from tracking your activity and storing personal data. However, similar to blocking cookies, it can also impair the functionality of many websites. You may experience issues with logging in, maintaining session states, and other personalized features. Some websites may not allow you to access their services at all if you do not accept cookies.

What Happens If You Accept Cookies in Incognito Mode?

When you accept cookies in incognito mode, the cookies are stored for the duration of your browsing session. However, once you close the incognito window, all cookies and browsing data are deleted. This means that while incognito mode can provide temporary privacy by not saving cookies permanently, it does not protect against cookie-based attacks within the session. Any cookies stored during the session can still be exploited if an attacker gains access to them before the session is closed.

Have Questions About 2FA and Cookies?

Bypassing 2FA with cookies is a sophisticated attack that exploits session cookies to bypass authentication mechanisms. Attackers use tools to create convincing phishing sites, extract session cookies, and gain unauthorized access to accounts. To protect yourself, always verify URLs, use strong security practices, and stay informed about the latest phishing techniques. By staying vigilant and informed, you can better defend against these evolving cyber threats. Still have questions about your IT security and safeguarding your company? Reach out, we are happy to talk to you about what Levelup can do for your business.