OS Credential Dumping

Adversaries may attempt to dump credentials to obtain account login and credential material, normally in the form of a hash or a clear text password, from the operating system and software. Credentials can then be used to perform Lateral Movement and access restricted information.

Several of the tools mentioned in associated sub-techniques may be used by both adversaries and professional security testers. Additional custom tools likely exist as well.

ID: T1003
Tactic: Credential Access
Platforms: Linux, Windows, macOS
Permissions Required: Administrator, SYSTEM, root
Data Sources: API monitoring, PowerShell logs, Process command-line parameters, Process monitoring
Contributors: Ed Williams, Trustwave, SpiderLabs; Vincent Le Toux
Version: 2.0
Created: 31 May 2017
Last Modified: 25 March 2020

Procedure Examples

Name Description
APT28

APT28 regularly deploys both publicly available (ex: Mimikatz) and custom password retrieval tools on victims.[18][19]

APT32

APT32 used GetPassword_x64 to harvest credentials.[20][21]

Axiom

Axiom has been known to dump credentials.[14]

Carbanak

Carbanak obtains Windows logon password details.[9]

HOMEFRY

HOMEFRY can perform credential dumping.[8]

Leviathan

Leviathan has used publicly available tools to dump password hashes, including HOMEFRY. [17]

OnionDuke

OnionDuke steals credentials from its victims.[11]

PinchDuke

PinchDuke steals credentials from compromised hosts. PinchDuke's credential stealing functionality is believed to be based on the source code of the Pinch credential stealing malware (also known as LdPinch). Credentials targeted by PinchDuke include ones associated many sources such as WinInet Credential Cache, and Lightweight Directory Access Protocol (LDAP).[11]

Poseidon Group

Poseidon Group conducts credential dumping on victims, with a focus on obtaining credentials belonging to domain and database servers.[15]

Revenge RAT

Revenge RAT has a plugin for credential harvesting.[12]

Sowbug

Sowbug has used credential dumping tools.[13]

Suckfly

Suckfly used a signed credential-dumping tool to obtain victim account credentials.[16]

Trojan.Karagany

Trojan.Karagany can dump passwords and save them into \ProgramData\Mail\MailAg\pwds.txt.[10]

Mitigations

Mitigation Description
Active Directory Configuration

Manage the access control list for "Replicating Directory Changes" and other permissions associated with domain controller replication. [4] [5]

Credential Access Protection

With Windows 10, Microsoft implemented new protections called Credential Guard to protect the LSA secrets that can be used to obtain credentials through forms of credential dumping. It is not configured by default and has hardware and firmware system requirements. [2] It also does not protect against all forms of credential dumping. [3]

Encrypt Sensitive Information

Ensure Domain Controller backups are properly secured.

Operating System Configuration

Consider disabling or restricting NTLM. [7]

Password Policies

Ensure that local administrator accounts have complex, unique passwords across all systems on the network.

Privileged Account Management

Windows:Do not put user or admin domain accounts in the local administrator groups across systems unless they are tightly controlled, as this is often equivalent to having a local administrator account with the same password on all systems. Follow best practices for design and administration of an enterprise network to limit privileged account use across administrative tiers.[1]

Linux:Scraping the passwords from memory requires root privileges. Follow best practices in restricting access to privileged accounts to avoid hostile programs from accessing such sensitive regions of memory.

Privileged Process Integrity

On Windows 8.1 and Windows Server 2012 R2, enable Protected Process Light for LSA.[6]

User Training

Limit credential overlap across accounts and systems by training users and administrators not to use the same password for multiple accounts.

Detection

Windows

Monitor for unexpected processes interacting with lsass.exe.[22] Common credential dumpers such as Mimikatz access the LSA Subsystem Service (LSASS) process by opening the process, locating the LSA secrets key, and decrypting the sections in memory where credential details are stored. Credential dumpers may also use methods for reflective Process Injection to reduce potential indicators of malicious activity.

Hash dumpers open the Security Accounts Manager (SAM) on the local file system (%SystemRoot%/system32/config/SAM) or create a dump of the Registry SAM key to access stored account password hashes. Some hash dumpers will open the local file system as a device and parse to the SAM table to avoid file access defenses. Others will make an in-memory copy of the SAM table before reading hashes. Detection of compromised Valid Accounts in-use by adversaries may help as well.

On Windows 8.1 and Windows Server 2012 R2, monitor Windows Logs for LSASS.exe creation to verify that LSASS started as a protected process.

Monitor processes and command-line arguments for program execution that may be indicative of credential dumping. Remote access tools may contain built-in features or incorporate existing tools like Mimikatz. PowerShell scripts also exist that contain credential dumping functionality, such as PowerSploit's Invoke-Mimikatz module, [23] which may require additional logging features to be configured in the operating system to collect necessary information for analysis.

Monitor domain controller logs for replication requests and other unscheduled activity possibly associated with DCSync. [24] [25] [26] Note: Domain controllers may not log replication requests originating from the default domain controller account. [27]. Also monitor for network protocols [24] [28] and other replication requests [29] from IPs not associated with known domain controllers. [4]

Linux

To obtain the passwords and hashes stored in memory, processes must open a maps file in the /proc filesystem for the process being analyzed. This file is stored under the path /proc//maps, where the directory is the unique pid of the program being interrogated for such authentication data. The AuditD monitoring tool, which ships stock in many Linux distributions, can be used to watch for hostile processes opening this file in the proc file system, alerting on the pid, process name, and arguments of such programs.

References

  1. Plett, C., Poggemeyer, L. (12, October 26). Securing Privileged Access Reference Material. Retrieved April 25, 2017.
  2. Lich, B. (2016, May 31). Protect derived domain credentials with Credential Guard. Retrieved June 1, 2016.
  3. NSA IAD. (2017, April 20). Secure Host Baseline - Credential Guard. Retrieved April 25, 2017.
  4. Metcalf, S. (2015, September 25). Mimikatz DCSync Usage, Exploitation, and Detection. Retrieved December 4, 2017.
  5. Microsoft. (n.d.). How to grant the "Replicating Directory Changes" permission for the Microsoft Metadirectory Services ADMA service account. Retrieved December 4, 2017.
  6. Microsoft. (2013, July 31). Configuring Additional LSA Protection. Retrieved February 13, 2015.
  7. Microsoft. (2012, November 29). Using security policies to restrict NTLM traffic. Retrieved December 4, 2017.
  8. FireEye. (2018, March 16). Suspected Chinese Cyber Espionage Group (TEMP.Periscope) Targeting U.S. Engineering and Maritime Industries. Retrieved April 11, 2018.
  9. Bennett, J., Vengerik, B. (2017, June 12). Behind the CARBANAK Backdoor. Retrieved June 11, 2018.
  10. Symantec Security Response. (2014, July 7). Dragonfly: Cyberespionage Attacks Against Energy Suppliers. Retrieved April 8, 2016.
  11. F-Secure Labs. (2015, September 17). The Dukes: 7 years of Russian cyberespionage. Retrieved December 10, 2015.
  12. Livelli, K, et al. (2018, November 12). Operation Shaheen. Retrieved May 1, 2019.
  13. Symantec Security Response. (2017, November 7). Sowbug: Cyber espionage group targets South American and Southeast Asian governments. Retrieved November 16, 2017.
  14. Novetta. (n.d.). Operation SMN: Axiom Threat Actor Group Report. Retrieved November 12, 2014.
  15. Kaspersky Lab's Global Research and Analysis Team. (2016, February 9). Poseidon Group: a Targeted Attack Boutique specializing in global cyber-espionage. Retrieved March 16, 2016.