Dictionary Attacks: How They Decode Passwords

Understanding Dictionary Attacks in Cybersecurity: Real-World Examples and Effective Mitigation

Understanding the tactics employed by malicious actors is crucial for effective cybersecurity. Against the backdrop of evolving threats and SOC challenges, including those related to organizational structure, outsourcing, and technology trends, this blog delves into one persistent security threat: dictionary attacks. Keep reading to explore the mechanics behind these password-cracking techniques, shed light on how they compromise online security, and give you advice on the best automated security solution to mitigate and defend against them.

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What is a Dictionary Attack?

Hacker thinking thrives on innovation, constantly devising new ways to breach supposedly secure systems. One kind of attack stems from the vulnerability of an organizations’ first line of defense – passwords. Dictionary attacks prey on vulnerabilities. And more often than not, take on the guessability factor of your password. 

Hackers thrive when organizations employ straightforward or predictable combinations for logins. They may start with common words found in a dictionary, like a pet’s name, birthday, or cherished icons. This is where the concept of a “dictionary attack” comes into play.

Online Dictionary Attack

Just as the title implies, online dictionary attacks occur when there’s a breach with an online entity. This could be a strike within the network service. Generally, online dictionary attacks are less viable because of the additional layer of security metrics and protocols implemented by entities. These include maximum log-in attempts and limited-time authentication. However, online dictionary attacks  become riskier, especially if there’s a leak of information.  

Offline Dictionary Attack

In an offline dictionary attack, there’s no correspondence with a server or system. Hackers can maximize their guessing efforts but the chance of detection is slim. With no definite limitations, this makes an offline dictionary attack similar to a guessing game- which requires a significant amount of effort considering the password possibilities are limitless.

How Dictionary Attacks Work 

A dictionary attack exploits common passwords or default logins to gain access to systems. These include simple phrases and easy number combinations like 123456, 111111, and password123. Through trial and error, hackers test each of the preselected passwords until they find the correct combination. 

Although a dictionary password attack is relatively simple compared to other cyber breaches, there’s still a high level of uncertainty for hackers. And this relates to the duration of the attack. It may take minutes, hours, or even days for the infiltration to occur. It largely depends on several factors, including the length of the word list.

Dictionary Attack Examples

Modification of Words

One of the major features of a dictionary attack is the manipulation of simple, single passwords. This is the reason why customization of words based on patterns is relevant to dictionary attacks. For example, hackers modify potential pre-listed passwords like default, default123, or default1234. However, replacing minimal characters is another way (instead of password, they try p@ssword or p@$$word). 

Relevance of a Word List

Now, hackers don’t stop at modifying words. Dictionary attackers also utilize test phrases related to the target audience. For instance, hackers targeting breaches across organizations use a couple of phrases associated with the city, such as iconic landmarks, sports teams, or notable descriptions of the city.

Examples of Dictionary Attacks

Dictionary attacks have plagued organizations worldwide. Some of the companies affected by this type of cyber attack include:

• Twitter (2009)
• LinkedIn (2012)
• Adobe hack (2013)
• Dropbox (2012)
• Ashley Madison (2015)

Why are Dictionary Attacks Successful?

In a digital landscape, convenience influences risk. This is particularly evident when choosing a password. It’s human nature to choose a simple password rather than keep track of complex login credentials. But, of course, the consequences of this can be severe. And that’s why dictionary attacks in cybersecurity are successful and recurrent, whether it’s about the usage of common phrases as passwords or the misalignment of technical skills. Even the cybersecurity talent shortage gives hackers an advantage.

Consequences of a Dictionary Attack

As with any cybersecurity breach, the implications of dictionary attacks on passwords are ominous. Some of the common repercussions of a dictionary attack include:

• Locked accounts
• Data loss
• Brand impersonation
• System damage
• Operational disruption
• Financial loss

Dictionary Attack Mitigation Strategies: How to Prevent Them 

Hackers capitalize on digital footprints efficiently. For this reason, it’s crucial for organizations to understand the best dictionary attack mitigation techniques to prevent breaches in their systems:

1. Choose a Unique Password

With Dictionary attacks focusing on  how passwords are set up, it’s important to choose the right combination. Be different, not predictable. Strengthen passwords by using a combination of unique characters, including symbols, numbers, and uppercase letters. 

2. Update Passwords Regularly

According to most experts, organizations should change passwords every few months. The lack of changing passwords regularly is a main factor for accounts that have been compromised. Outdated accounts and passwords are a hacker’s dream.

3. Get Help from a Password Manager 

Using a password manager is another technique to prevent dictionary attacks. Through this tool, memorizing passwords isn’t needed. The system does the work for you, making log-ins much easier. Aside from automating the process and filling in all key details, password managers improve overall security.

4. Try Biometric Identification 

Biometrics offers a more secure way of authenticating an account. It uses physical features for authentication, including face, fingerprint, retina, and vein. By leveraging physical authentication methods such as fingerprint matching or facial recognition, it renders dictionary attacks impractical. Biometric authentication is widely used on mobile devices, especially for banking apps and payments.

5. Take advantage of Rest API Authentication

Rest API Authentication is the process of verifying the identity of a user or client before granting access to a REST API, a type of web API that follows the Representational State Transfer (REST) architectural style. REST is a set of guidelines that define how applications or devices can connect and communicate with each other. Some of these authentication methods help defend against dictionary attacks are:

• Enforcing strong password policies that require passwords of a certain length and complexity.
• Implementing rate limiting, or account lockout policies, to make it more difficult for attackers to brute-force passwords. This feature automatically locks the account after several failed log-in attempts. 
• Using CAPTCHA challenges that are designed to be difficult for computers to solve but easy for humans to solve, preventing automated dictionary attacks.
• Implementing two-factor authentication (2FA), a mitigation technique that adds an extra layer of security to accounts through the usage of an OTP.
• Avoiding username enumeration to prevent attackers from being able to determine whether a given username exists. This can be done by obscure error messages and avoiding responses that indicate whether a username is valid or not.
• Using strong password hashing. A process of encrypting passwords that makes them difficult to crack. Strong password hashing algorithms use a salt ( a random value that is unique to each password), making it more difficult for attackers to crack passwords using rainbow tables.

How Dictionary Attacks Differ from Other Cybersecurity Attacks

While dictionary attacks generally highlight how passwords are set, there’s a fine that makes it unique. Although dictionary attacks are associated with other types of cybersecurity attacks, it’s important to distinguish them.

Dictionary Attack vs Brute Force

The difference between a brute force and a dictionary attack is distinguished by the manner of the attack. A brute-force attack exhausts all password possibilities.

Although randomness significantly influences the process, it may result in longer completion times. Additionally, compared with a dictionary attack, it targets a single user.

Password Spraying vs Dictionary Attack

Password spraying is a dictionary attack that uses common patterns and frequently used passwords, such as birthdates, names, and common phrases. It gains access to the system using the same password across all accounts. Unlike dictionary hacking, this type has a lower success rate, especially on systems and accounts with longer, more complex passwords.

Rainbow Table vs Dictionary Attack

Featuring a precomputed table of password options, a rainbow table attack targets specific hashes and plaintexts. A rainbow table password attack can compromise the system as long as the password is within the algorithm’s hash space. 

A hacker, prompted by an outdated password in the target application, uses password hashes to generate a rainbow table to decrypt all users’ passwords. The risk of a rainbow table attack lies in its greater storage requirements and longer table creation time.

What are Dictionary Attack Solutions? 

The digital world’s evolution drives technology development and the growth of advanced hacking techniques, exemplified by numerous readily available dictionary attack tools, some even accessible online for free, posing a threat to system security.

With the surge of these tools, the threat readiness of organizations is more important than ever. SecOps teams must level-up their security posture and partner with a trusted brand, like Swimlane.

Empower Your Organization’s Security with Swimlane Turbine

Keeping your cybersecurity landscape safe and up-to-date is crucial. With the help of Swimlane Turbine, you get the perfect combination of human and machine intelligence with AI automation. Our modern approach to security automation ensures flexibility, seamless integrations, and actionable insights. Implementing Swimlane Turbine protects your business from dictionary attacks and other common SecOps challenges.