Skip to content

OS Credential Dumping

What is OS Credential Dumping?

OS Credential Dumping refers to the process by which a malicious actor extracts authentication credentials like usernames and passwords from the operating system. This can include retrieving plaintext passwords, hashed passwords, authentication tokens, and other forms of credentials directly from the memory (RAM) or from various system files.

How is OS Credential Dumping Performed?

  1. Memory Scraping:

  2. Attackers use tools to read memory of running processes directly. Tools such as Mimikatz can extract credentials from memory associated with authentication processes like lsass.exe in Windows.

  3. Accessing Security Databases:

  4. On Windows systems, attackers might extract hashes and credentials from the Security Account Manager (SAM) database or the SYSTEM registry hive.

  5. Tools like pwdump, samdump2 are commonly used for this purpose.

  6. Extracting Cached Credentials:

  7. In environments where users log in while offline, Windows stores a version of user's hash in cache. Tools can also target these cached credentials.

  8. Hooking Techniques:

  9. By installing hooks on API functions that handle authentication data, attackers can capture credentials as they are accessed by legitimate processes.

  10. Dumping Keychain Data:

  11. On macOS, keychain stores encrypted passwords and secure notes. Tools like keychaindump can be used to extract these credentials if access permissions are obtained.

  12. Stealing Linux Credentials:

  13. In Linux, /etc/shadow file stores hashed user password information which can be targeted.
  14. Memory scraping techniques similar to those used on Windows can also be applied using tools tailored for Linux environments.

Where is OS Credential Dumping Typically Used?

OS Credential Dumping is typically employed in environments where gaining higher-level access to network resources is necessary for fulfilling an attacker’s objectives such as lateral movement within a network or escalating privileges. It's commonly seen in targeted attacks against enterprises where prolonged access or data exfiltration requires administrative privileges.

Why is OS Credential Dumping Significant?

  • Bypass Authentication Systems: By obtaining actual user credentials, attackers can bypass authentication mechanisms undetected as legitimate users.
  • Privilege Escalation: Access to administrative accounts allows deeper penetration into systems and networks, enabling further malicious activities.
  • Lateral Movement: With valid credentials, attackers can move across the network accessing critical systems without raising alarms typically triggered by exploit activities.
  • Persistence: Having legitimate credentials allows attackers to re-enter the network multiple times without needing to re-exploit already patched vulnerabilities.

This technique underscores the need for robust security measures including but not limited to regular password changes, employing multi-factor authentication, securing memory access on critical machines, and monitoring abnormal access patterns within networked environments.