4 ways hackers can break 2FA—and why you should still use it anyway

Two-factor authentication (2FA) is widely recognized as a crucial security measure to protect against hackers. Even if your password is stolen or guessed, another checkpoint will block account access, providing an extra layer of defense. However, no security measure is foolproof, and attackers have discovered ways to sidestep 2FA's stronger protection.

Let's explore four common methods used by hackers to break 2FA, along with some practical tips on how to avoid these vulnerabilities:

The Simplest Form of 2FA: SMS-based Codes

Sending one-time codes over text message is considered one of the weakest forms of 2FA. These messages can be intercepted in various ways, making them vulnerable to attacks.

  • SIM jacking: A hacker steals your phone number and contacts your carrier to link it to a new SIM card or eSIM. They then receive all text messages, including 2FA codes.
  • SS7 attack: The SMS message is redirected, making it impossible to directly avoid this type of attack due to the way messaging protocols work.

To guard against SIM jacking, contact your phone carrier's customer support and ask if you can create a special account PIN or password that will be required for any account changes, including switching to a new SIM card. However, using SMS-based 2FA is inherently flawed due to the limitations of telecommunication systems.

Phishing Attacks: A Common Method to Break 2FA

Another way hackers can break 2FA is through phishing attacks, which aim to steal both your password and your 2FA codes. If you type or enter this information into a fake or compromised login page, the hacker gains access to your account.

To avoid falling victim to phishing attacks:

  • Be cautious about which websites you visit and the forms you fill out.
  • Refuse to give your code to anyone who asks. If someone calls or contacts you, verify their identity before sharing any sensitive information.
  • Avoid downloading apps or browser extensions not widely recommended by experts, as they may silently steal your 2FA codes.

The Most Secure Form of 2FA: Security Keys

Security keys, such as Yubikeys, are considered the most secure form of 2FA. You need to be physically present to use one and successfully authenticate during the 2FA verification step – unless an attacker gets their hands on your security key.

However, even with security keys, hackers can exploit a weaker form of 2FA: verifying new devices from an already authorized device. By launching an approval spamming attack, hackers can bypass this additional layer of protection.

Premutationary Precautions

To avoid falling victim to these types of attacks, consider the following:

  • Use unique, strong passwords for your accounts.
  • Keep your security keys and devices up-to-date with the latest software updates and firmware patches.
  • Disable any weaker forms of 2FA, such as SMS-based codes, and stick to more secure methods like security keys or alternative verification methods.

In conclusion, while no security measure is foolproof, being aware of these common vulnerabilities and taking preventative measures can help you avoid falling victim to 2FA-breaking attacks. By prioritizing your online security, you'll be better protected against the ever-evolving threats in the digital landscape.