Common Types Of Password Attacks and How to Defend Yourself

Brute-Force Attack

Concept: Hackers systematically try every possible combination of characters until they crack the password. This is like trying every key on a keyring.

Here are some variants of a brute-force attack:

• Simple Brute Force: Testing all possible character combinations sequentially
• Hybrid Brute Force: Combining dictionary words with brute-force techniques (e.g., "password123!", "Welcome2026")‍
• Reverse Brute Force: Using known passwords to discover matching usernames across multiple accounts

How to Avoid: Use strong, complex passwords with a mix of uppercase and lowercase letters, numbers, and symbols to make brute-forcing immensely time-consuming. Implement credential rotation policies to ensure that even if a password is eventually cracked, it will no longer be valid. Enable multi-factor authentication (MFA) to add an extra layer of security beyond just the password. Implement account lockout policies that temporarily disable accounts after multiple failed login attempts, and use rate limiting to slow down automated attack tools.

The Electronic Frontier Foundation's DES Cracker (1998): This is a real-world example of how advancements in technology can render encryption algorithms weak. The EFF built a machine specifically designed to crack DES keys through brute-force, highlighting the vulnerability of DES and pushing for the development of stronger encryption standards like AES. This event serves as a reminder of the importance of using robust encryption and constantly evolving security practices.

Dictionary Attack

Concept: Hackers try common words and phrases found in dictionaries or leaked password databases.

Attackers often customize their wordlists based on their target. For example, when attacking a healthcare organization, they might include medical terminology, or when targeting a specific company, they'll add company names, product names, and industry jargon. These targeted wordlists, sometimes called "spidering attacks," dramatically increase success rates.‍

How to Avoid: Avoid using dictionary words, personal information (such as birthdays and addresses), and simple keyboard patterns. Consider using passphrases, random combinations of 4–6 unrelated words, which are both easier to remember and harder to crack than traditional passwords. According to NIST guidelines, passphrases of 15+ characters provide significantly stronger protection than shorter complex passwords. NIST emphasizes length and memorability first, and treats character complexity as optional rather than a strict requirement.

Password Spraying Attack

Concept: Unlike brute-force attacks that try many passwords against one account, password spraying tries a small number of commonly used passwords (like "Password123", "Summer2026!", or "Welcome1") against many accounts simultaneously. This technique is specifically designed to evade account lockout policies, which typically trigger after several failed attempts on a single account.

Password spraying is difficult to detect because it distributes login attempts across many accounts, staying below lockout thresholds. Attackers often wait between attempts, sometimes cycling through targets over days or weeks to avoid triggering security alerts.

How to Avoid: Ban commonly used passwords and implement password blacklists. Use behavioral analytics to detect distributed login anomalies. Enable MFA across all accounts, especially privileged ones. Monitor for unusual patterns such as login attempts from unexpected locations or unusual times. Implement passwordless authentication to eliminate password-based vulnerabilities entirely.

Credential Stuffing Attack

Concept: Hackers leverage stolen username and password combinations (often from data breaches) to try them on other accounts.

With billions of leaked credentials available on the dark web, attackers use automated tools to test these combinations across hundreds of websites simultaneously. The attack exploits the widespread habit of password reuse, and industry research shows that over 60% of users reuse passwords across multiple accounts.‍

How to Avoid: Never reuse passwords across different accounts. If you suspect one of your accounts has been compromised, change the password immediately. Use unique and strong passwords for every account. Organizations should implement credential screening services that check passwords against known breach databases during account creation and login.

Phishing Attack

Concept: Hackers trick users into revealing their login credentials through deceptive emails, messages, or fake websites. Credential phishing is one of the most prevalent forms of this attack, where attackers create convincing login pages to steal usernames and passwords.

Here are some variants of a phishing attack:

• Spear Phishing: Highly targeted attacks using personal information about specific individuals
• Clone Phishing: Duplicating legitimate emails but replacing links and attachments with malicious ones
• Vishing (Voice Phishing): Phone calls impersonating trusted entities to extract credentials
• Smishing (SMS Phishing): Fraudulent text messages containing malicious links‍
• Typosquatting/URL Hijacking: Registering domains similar to legitimate sites (e.g., "arnazon.com" instead of "amazon.com") to capture mistyped URLs
  

How to Avoid: Be cautious of emails or messages urging immediate action or requesting personal information. Don't click on suspicious links or attachments. Verify website legitimacy before entering login details. Implement phishing-resistant MFA that uses cryptographic authentication methods, making it impossible for attackers to intercept or reuse credentials even if users fall for phishing attempts.

Keylogger Attack

Concept: Hackers install malware that records your keystrokes, capturing passwords and other sensitive information.

Keyloggers can be either software-based (installed via malicious downloads, email attachments, or compromised websites) or hardware-based (physical devices attached to keyboards or computers). Software keyloggers are far more common and can be bundled with seemingly legitimate applications, especially those downloaded from unofficial sources.‍

How to Avoid: Use antivirus and anti-malware software with real-time protection. Be cautious when downloading files or clicking on links from unknown sources. Only download software from official sources and verified publishers. Consider using virtual keyboards for entering sensitive credentials on potentially compromised devices. Passwordless authentication methods like biometrics or hardware security keys are immune to keylogger attacks since there's no password to capture.

Man-in-the-Middle Attack (MitM)

Concept: Hackers intercept communication between your device and a website, potentially stealing login credentials. This can happen on unsecured Wi-Fi networks.

A variation of MitM attack is

‍Traffic Interception: A variation of MitM attacks where attackers passively eavesdrop on network traffic to capture data in transit. This is particularly effective on networks using unencrypted protocols (HTTP instead of HTTPS) or when attackers can compromise network infrastructure. Even SSL/TLS traffic can be vulnerable through techniques like SSL hijacking, where attackers create a bridge between the user and their destination to intercept encrypted communications.

‍How to Avoid: Avoid using public Wi-Fi for sensitive transactions. Use a Virtual Private Network (VPN) to encrypt your internet traffic on public Wi-Fi. Always verify that websites use HTTPS (look for the padlock icon) before entering credentials. Enable router encryption on home and office networks. Organizations should implement certificate pinning and network segmentation to limit the impact of compromised connections.

Rainbow Table Attack

Concept: Hackers pre-compute hashes (mathematical transformations of passwords) for common passwords. They then compare these pre-computed hashes to stolen password hashes to potentially crack the passwords.‍

How to Avoid: Creating strong, complex passwords mitigates the effectiveness of rainbow tables. Additionally, reputable websites should store passwords securely using a one-way hashing function, making them unreadable even in a data breach.

Organizations should implement password salting, adding unique random data to each password before hashing, which makes rainbow tables ineffective since each password produces a unique hash even if the original passwords are identical. Modern hashing algorithms like bcrypt, scrypt, or Argon2 provide built-in salting and are designed to be computationally expensive, further protecting against offline cracking attempts.

Real-World Examples of Password Attacks

2013 Adobe Breach

Over 150 million user accounts were compromised due to a combination of weak password hashing and a successful phishing attack that obtained employee credentials. This incident highlights the importance of both strong passwords and robust security measures to protect user data.

2014 Yahoo Breaches

Billions of user accounts were exposed in a series of attacks, likely involving a combination of techniques like social engineering and password guessing. This emphasizes the need for user awareness about social engineering tactics and the importance of creating complex passwords that resist guessing.

2017 Equifax Breach

A data breach exposed sensitive information of over 147 million Americans, potentially due to a vulnerability in a web application that allowed attackers to exploit weak passwords. This example underscores the critical role of web application security in protecting user data and the dangers of weak passwords.

2024 Microsoft Midnight Blizzard Attack

Russian state-sponsored hackers used password spraying to compromise Microsoft's corporate systems. The attackers accessed email accounts of senior leadership and employees in cybersecurity and legal departments, demonstrating that even sophisticated organizations are vulnerable when password-based authentication is the primary defense.

2024 Roku Credential Stuffing Incidents

Over 591,000 Roku customer accounts were compromised across two separate credential stuffing attacks. Hackers used username-password pairs stolen from other data breaches to access accounts, with some attackers making fraudulent purchases using stored payment information.

Moving Beyond Passwords

While strong passwords and MFA significantly reduce risk, many organizations are now adopting passwordless authentication to eliminate the primary target that attackers exploit. Methods like biometrics, hardware security keys (FIDO2/WebAuthn), and cryptographic certificates remove passwords from the equation entirely. This makes phishing, credential stuffing, and password spraying ineffective since there's no password to steal or guess.

Organizations considering this approach should transition gradually, supporting both traditional and passwordless methods until full migration is complete.

FAQs

1. Why should my business be concerned about password attacks?

Password attacks are a major threat to businesses. Stolen login credentials can grant attackers access to sensitive data, financial resources, and even your entire IT infrastructure. This can lead to financial losses, reputational damage, and legal repercussions.

2. Are some businesses more vulnerable than others?

Any business that stores sensitive data or uses online accounts is at risk. However, businesses with weak password policies, outdated security practices, or a lack of employee awareness training are more susceptible.

3. What are some common ways hackers target businesses with password attacks?

Hackers employ a variety of tactics, including:

• Phishing attacks: Targeting employees with emails or messages designed to trick them into revealing login credentials.
• Credential stuffing attacks: Using stolen login information from other breaches to try gaining access to business accounts.
• Malware attacks: Deploying malware that can steal passwords or keystrokes from employee devices.
• Password spraying: Testing common passwords across many employee accounts to find weak credentials while avoiding account lockouts.

4. How can my business defend against password attacks?

Here are some key strategies:

• Implement a strong password policy: Enforce minimum password length, complexity requirements, and regular password changes.
• Enable multi-factor authentication (MFA): This adds an extra layer of security beyond just the password. Follow best practices for MFA implementation to ensure proper deployment and maximum security benefit.
• Educate employees about password security: Train them to recognize phishing attacks, avoid password reuse, and use strong passwords.
• Use a password manager for business: This allows employees to create and store strong, unique passwords securely.
• Regularly update software and security solutions: Patch vulnerabilities promptly to minimize attack vectors.
• Segment your network: Limit access to sensitive data and systems to authorized personnel only.
• Monitor for suspicious activity: Implement security tools that can detect unusual login attempts or data breaches.
• Implement account lockout and rate limiting: Automatically disable accounts after multiple failed login attempts to prevent brute-force attacks.
• Deploy behavioral analytics: Use tools that detect anomalous login patterns, such as attempts from unusual locations or times.
• Consider passwordless authentication: Explore biometric, hardware token, or certificate-based authentication to eliminate password vulnerabilities entirely.

5. What should we do if we suspect a password attack?

If you suspect a successful password attack, take immediate action:

• Isolate compromised accounts and change passwords.
• Investigate the source of the attack and take steps to prevent future breaches.
• Notify relevant authorities and potentially affected customers.
• Review access logs to determine the scope of the breach and identify all affected systems.
• Implement additional authentication requirements for affected users upon password reset.