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Credentials from Web Browsers

What: Credentials from Web Browsers

Credentials from Web Browsers refers to the process and techniques used by attackers to extract user credentials (such as usernames, passwords, and other authentication tokens) directly from web browsers. This can include credentials saved by the browser or cached during active sessions.

How: Techniques and Mechanisms

  1. Accessing Browser Password Stores: Most modern web browsers offer to save passwords for users. These passwords are stored in an encrypted format specific to each browser. For example:

  2. Google Chrome uses a SQLite database file (Login Data), and starting from version 80, it encrypts this file using AES-256, with a key stored in the system's keychain.

  3. Mozilla Firefox stores passwords in two files: logins.json for the actual data and key4.db for the encryption key.

  4. Extracting Session Cookies: If an attacker can access session cookies, they can impersonate a user without needing their password. Tools like browser extensions or malware can be used to read these cookies directly from an active session.

  5. Hooking Browser Processes: By injecting malicious code into browser processes (using techniques like DLL injection), attackers can intercept function calls that handle sensitive information, including passwords and session tokens.

  6. Phishing Extensions: Malicious browser extensions can be designed to log keystrokes, capture screenshots of web pages, or redirect users to phishing sites where credentials are harvested directly.

  7. Browser Memory Scraping: By accessing memory used by the browser while it is running, sensitive information such as passwords and encryption keys can be extracted before they are cleared from memory.

Where: Attack Surfaces

  • Local Access: An attacker with physical or remote access to a user's machine can directly access the file system and memory where browsers store sensitive data.
  • Browser Extensions: The extension ecosystem of browsers is another vector; malicious extensions can be installed either through deceptive practices or by exploiting vulnerabilities in legitimate extensions.
  • Network Interception: Man-in-the-middle (MITM) attacks on insecure network connections allow attackers to intercept data being sent to and received from web servers, including cookies and potentially other credentials if not properly secured with HTTPS.

Why: Motivations Behind Attacks

  1. Financial Gain: Accessing someone’s financial accounts directly or selling their credentials on dark web markets.
  2. Identity Theft: Using stolen identities for committing fraud or other illegal activities.
  3. Corporate Espionage: Stealing business-critical information or gaining unauthorized access to competitor’s resources.
  4. Personal Attacks: Targeted attacks for personal reasons, often involving stalking or harassment.

This sub-category of attack is critical because it targets what is essentially the keys to online identity and services, making it one of the most impactful methods of cybercrime today due to its potential direct access to sensitive information without needing more sophisticated breach methods once initial access has been gained through credential theft.