How to Prevent Brute Force Attacks

Industry News

A brute force attack is one of the most straightforward and least sophisticated hacking methods. The hacker aims to gain unauthorized access to an account by guessing different combinations of the username/email and password. It uses a trial-and-error method and attempts to log in with different combinations repeatedly until it succeeds.


Usually, the hacker’s motive behind a brute force attack is to use the compromised account to spread malware, steal sensitive information, disrupt services, or a combination of the three. In order to identify brute force attacks, you just need to keep an eye on your Apache access log or Linux log files. You should be alerted as soon as you notice someone attempting to log in to your account multiple times without success in a short period of time.


Brute force attacks may also be happening if:

  • Unusual pattern of failed login attempts
  • Failed login attempts from the same IP address into many accounts
  • Logging into an account from an unknown IP address
  • A successful login followed by numerous failed login attempts
  • Unusual user behavior after a successful login
  • Increased internet use after a successful login


How to Prevent Brute Force Attacks 


1. Use Strong Passwords

The more complex the password, the longer time it takes to crake. It is recommended to use a password that is 8 – 16 characters in length, with a random mix of uppercase, lowercase letters, numbers and signs. Don’t recycle passwords for your accounts and remember to change them from time to time.


2. Limit the Number of Failed Login Attempts

If an account exceeds a certain number of unsuccessful login attempts, you can lock the account or ban the IP address for a considerable length of time, forcing the user to confirm identity with multi-factor authentication or contact an administrator. 



Captchas are now widely used on websites to differentiate between spam computers and legitimate users. It requires users to enter a phrase or click a specific item on a generated image, preventing bots from executing automated scripts, which are mainly used in Brute Force attacks.


4. Use Two-Factor Authentication (2FA)

Adding a second authentication factor makes it far more difficult for a hacker to brute force an account. Even if the hacker enters the correct login and password, 2FA requires first confirming a user’s identity by entering a one-time SMS code or a biometrics scan like a fingerprint scan before being granted access. These unique authentication factors are difficult to obtain or forge.


5. Keep Track of All Activity Within Your Network

Monitoring user and entity activity within your network enables you to spot brute force attack signals such as credential stuffing, lateral movement, frequent access requests, and more. You may set up monitoring in two different ways: by keeping an eye on user behavior or by monitoring network events. Web admins should carefully examine your server log files.


6. Only Allow Logins From a Specific IP Address or Range

Making a whitelist of user IP addresses and blocking unknown connections can be a good strategy. Brute force attackers will have to work hard to get past that barrier and gain access. Whitelisting IP addresses, on the other hand, will not work effectively for remote users who frequently access the organization’s network from personal devices and in different places. You can set up a VPN if you don’t have a static IP address. But for some use cases, this approach might not be suitable.

We have several security precautions in place to defend our clients from brute force attacks. To learn more, don’t hesitate to get in touch with our customer service by phone at +852 3959 1800 or via email at