Introduction: What is brute force?
There are a variety of threats in the world of cyber security, but few are as basic and terrifying as the brute force method. This type of attack aims to use brute force to try all possible combinations of a password or encryption until the right one is found. The simplicity and associated efficiency make brute force a particularly insidious threat that can sneak through modern security mechanisms.
Definition and basic principles of the brute force method
Brute force is a technique in which an attacker systematically tries all possible combinations of passwords or keys in order to gain access to a protected system. It is based on the assumption that all possible options will be tried at some point until the correct one is found. This method utilises the processing power of modern computers to tirelessly and comprehensively test all possible combinations. Despite its simplicity, brute force can be particularly successful if the passwords used are weak or insufficiently complex.
How long does it take an attacker to get your password?
This question is not easy to answer. Because it depends on the use case. For example, brute forcing via a login page can take longer than guessing a password using bcrypt. The following table shows an example of how long it takes to brute force a password of a certain length using bcrypt.
How brute force attacks threaten cyber security
Brute force attacks pose a significant threat to cyber security as they undermine the basic principles of access control. Attackers can use this method to gain access to sensitive data, compromise systems and cause major damage. The threat of brute force is particularly acute in systems that are not adequately protected against repeated login attempts or where simple passwords are used. Due to the constant increase in computing power and the availability of powerful hardware, brute force attacks can be carried out more and more efficiently.
Historical overview: The development of brute force attacks
Brute force attacks are not a new phenomenon; they have existed since the early days of computing. In the early days of computer technology, passwords were often short and relatively simple, which made the method particularly effective. With the development of more complex encryption techniques and the introduction of modern security protocols, brute force attacks have become more difficult and time consuming. Nevertheless, by utilising more computing power and more sophisticated algorithms, attackers have found ways to overcome the challenges. Today, brute force attacks are more dangerous than ever thanks to the enormous computing power of modern computers and the proliferation of powerful GPUs.
The different types of brute force attacks
Brute force attacks are not monolithic, but are divided into different types depending on the attack target and method. These types vary in their complexity and effectiveness:
Individual password attempts: How they work and why they're dangerous
During a single password attempt, the attacker tries one password entry after another until the correct combination is found. This method can be extremely time-consuming, but is often successful with simple passwords or poorly secured systems. The danger of this method lies in the fact that it works systematically and considers every possible combination, which leads to a high success rate with inadequately secured systems.
Dictionary attacks: Use of ready-made lists
Dictionary attacks use ready-made lists of passwords that are frequently used in practice. These lists contain common passwords, phrases and variations based on the assumption that many users choose simple and frequently used passwords. By browsing such lists, an attacker can quickly access common passwords, making this method particularly effective for systems that do not have strict password requirements.
Rainbow Tables: An overview of pre-stored hashes
Rainbow tables are an advanced technique for accelerating brute force attacks by using pre-stored hashes. Instead of re-hashing and verifying each password, attackers use a table that already contains the hash values of many possible passwords. This allows a quick search for the original password by searching the table for matches. Rainbow tables pose a significant challenge for systems that do not have adequate defences against prefabricated hashes.
Hybrid attacks: combination of dictionary and brute force
Hybrid attacks combine elements of dictionary and brute force attacks by first going through a dictionary list and then performing additional brute force attempts. This method utilises the strengths of both types of attack to increase efficiency. The attacker starts with common passwords and variations and then switches to full brute force tests if simple attempts fail.
Targeted brute force attacks: Focussing on specific targets
In targeted brute force attacks, the attacker focuses on specific targets or systems, often using specific information about the target. This can be done through social engineering or gathering information about the target to guess specific passwords or combinations. This method is particularly dangerous as it is based on the vulnerabilities of the specific target and often leads to successful attacks.
Signs of possible attacks on your system
Possible attacks on your system can be recognised by several signs, including unusual login activity, repeated failed login attempts and suspicious IP addresses. Sudden changes in access patterns or the occurrence of system errors can also indicate a brute force attack. Proactive surveillance and effective monitoring are therefore essential in order to be able to react to possible attacks at an early stage.
Monitoring and analysis: How to identify suspicious activity
Continuous monitoring and analysis of system activities are crucial in order to identify suspicious activities in good time. By using security software, log analysis and behavioural analysis, administrators can detect unusual patterns or anomalies. Automated tools and intelligent threat detection systems help to identify potential brute force attacks at an early stage and initiate appropriate measures.
Protective measures against brute force attacks
Various protective measures are required to arm yourself against brute force attacks. Implementing and regularly updating these measures can significantly reduce the likelihood of a successful attack.
Strong passwords: the first line of defence
Strong passwords are the first and most important line of defence against brute force attacks. A password should consist of a combination of upper and lower case letters, numbers and special characters and be of sufficient length. A strong password significantly reduces the likelihood of an attacker being able to determine it by brute force.
Multi-factor authentication: an additional protective shield
Multi-factor authentication (MFA) provides an additional layer of protection by requiring a second verification factor in addition to the password. This can be a code from a mobile device or a biometric feature such as a fingerprint. MFA makes it much more difficult for attackers to gain access to a system, even if they know the password.
Rate limiting: Limiting the number of login attempts
Rate limiting restricts the number of login attempts that can be made from a single IP address in a certain period of time. This measure reduces the effectiveness of brute force attacks, as the attacker is forced to take a break or use a different IP address after a certain number of failed attempts.
CAPTCHAs: Protection by confirming that the user is human
CAPTCHAs (Completely Automated Public Turing test to tell Computers and Humans Apart) are tests that ensure that the user is a human and not an automated script. They represent a further barrier against brute force attacks by blocking automated attempts and making access more difficult for attackers.
IP blocking and geoblocking: access control by location
IP blocking and geo-blocking are methods of controlling access to a system based on the IP address or geographical location of the user. These measures can help to prevent unwanted or suspicious access attempts and thus reduce the attack surface.
Regular security checks and password changes
Regular security checks and password changes are essential measures to ensure the security of a system. By regularly checking security logs and updating passwords, vulnerabilities can be identified and rectified before they can be exploited by attackers.
Security software and firewalls: your first line of defence
Security software and firewalls provide a first line of defence against brute force attacks. These tools monitor traffic, block suspicious activity and protect against unauthorised access. Regular updating and configuration of these security solutions are critical to protecting against brute force and other threats.
Encryption of passwords: protection through hash algorithms
Encrypting passwords using hash algorithms is a tried and tested method for protecting passwords in databases. By using hash functions, passwords are converted into unreadable hash values that cannot be easily converted back. This makes it more difficult for attackers to decrypt passwords using brute force.
Best practices for password management and creation
Following best practices for password management and creation is critical to protecting against brute force attacks. This includes using password managers, creating unique and complex passwords and updating passwords regularly.
Tips for choosing secure passwords
When choosing secure passwords, complex combinations of letters, numbers and special characters should be used. It is also advisable to change passwords regularly and not to use personal or easily guessable information.
Recommended password managers for managing complex passwords
Password managers are indispensable tools for managing complex passwords. They store and generate secure passwords and facilitate the use of different, unique passwords for different accounts. Choosing a trustworthy password manager can help to significantly increase security.
Common mistakes when protecting against brute force and how to avoid them
Common mistakes in protecting against brute force attacks include using weak passwords, neglecting security updates and not using multi-factor authentication. Avoiding these mistakes requires a conscious effort, ongoing training and regular security audits.
How companies can arm themselves against brute force attacks
Companies can arm themselves against brute force attacks by implementing comprehensive security guidelines and organising regular training for employees. This includes the introduction of strict password requirements, the use of security software and the establishment of emergency plans.
Security guidelines and training for employees
Implementing strict security policies and regular training for employees is crucial to protect against brute force attacks. Training should cover topics such as creating secure passwords, recognising phishing attempts and dealing with suspicious activity.
Emergency plans and response strategies in the event of a brute force attack
In the event of a brute force attack, it is important to have contingency plans and response strategies in place. These should include clear instructions for identifying, containing and remediating the attack. An effective contingency plan can help to minimise the damage and speed up the recovery of the system.
Summary and recommendations for action
To summarise, it is essential to be aware of the threat of brute force attacks and to take appropriate protective measures. Strong passwords, multi-factor authentication, rate limiting and regular security checks are crucial measures to protect against such attacks. Continuous improvement and adaptation of security strategies is the key to effective protection.
Summary of the most important protective measures
The most important protective measures include the implementation of strong passwords, the use of multi-factor authentication, rate limiting, CAPTCHAs, IP blocking and geo-blocking as well as the regular review and updating of security protocols.
Next steps: Implementation and continuous improvement
The next step is the practical implementation of the protective measures described and the continuous monitoring of their effectiveness. The regular adaptation and improvement of security strategies and the training of employees are crucial for comprehensive protection against brute force attacks.
