Libsam
Overview
Executive Summary
Libsam (often a component of or detected alongside tools like `pwdump` or `gsecdump`) is a classification for a HackTool library designed specifically to interact with and extract the Security Account Manager (SAM) database from Windows operating systems. When found on a corporate endpoint outside of authorized penetration testing, it is a critical indicator of post-compromise activity and impending credential theft.Technical Capabilities and Abuse
Libsam itself is typically a Dynamic Link Library (`.dll`) utilized by a larger credential dumping framework. Threat actors deploy these tools *after* they have already achieved local Administrator or SYSTEM privileges on a compromised machine. Its primary function is the circumvention of OS protections to facilitate hash extraction:- SAM Database Interaction: The Windows SAM file stores user passwords in a hashed format (LM/NTLM). Normally, the OS locks this file while Windows is running. Libsam provides the low-level API calls necessary for a dumping tool to bypass this lock.
- Injection and Extraction: The tool utilizing Libsam often injects into the Local Security Authority Subsystem Service (`lsass.exe`) process or utilizes specialized drivers to dump the hashes directly from memory or the registry without needing to read the physical SAM file on disk.
- Facilitating Lateral Movement: The extracted NTLM hashes are then exfiltrated. Attackers can use them in offline cracking attacks (using Hashcat) or directly in "Pass-the-Hash" attacks to authenticate to other servers and pivot laterally across the Active Directory domain.
Threat Assessment
The unauthorized presence of Libsam (or associated credential dumping utilities) on a system is a critical security emergency. It unequivocally indicates that an attacker has achieved elevated privileges and is actively attempting to steal domain credentials to facilitate widespread lateral movement.Incident Response and Remediation
- Immediate Network Isolation: Isolate the compromised machine immediately to prevent the attacker from exfiltrating the dumped hashes or using them to pivot to the Domain Controller.
- Enterprise-Wide Credential Reset: If the tool executed successfully, incident responders must assume that all local accounts (and potentially cached domain accounts) on that machine are compromised. A mandatory password reset must be enforced.
- Hunt for the Initial Access Vector: Libsam is a post-exploitation tool. The investigation must focus on *how* the attacker gained the administrative privileges necessary to deploy it in the first place (e.g., exploiting a vulnerable service, phishing a privileged user, or lateral movement from another host).
Known aliases
Threat reports may refer to this family under multiple names:
MITRE ATT&CK Techniques
This family has been observed using the following ATT&CK techniques: T1003.002 T1003.001 T1550.002
Tactical Mitigations
Based on the techniques used by this family, consider the following defensive strategies:
- T1003.001: Monitor for LSASS memory dumping or registry SAM extraction. Enable Credential Guard on Windows systems.
- T1003.002: Monitor for LSASS memory dumping or registry SAM extraction. Enable Credential Guard on Windows systems.
Generated Detections (Boilerplate)
These YARA and Sigma rules are auto-generated based on the family name and aliases. They must be heavily tuned before deployment in a production environment.
YARA Rule
rule MALWARE_WIN_LIBSAM {
meta:
description = "Detects Libsam (advanced_threat)"
author = "SystemHelpdesk Boilerplate Generator"
date = "2026-07-06"
strings:
$s1 = "libsam" ascii wide nocase
$s2 = "hacktool.libsam" ascii wide nocase
$s3 = "riskware.pwdump.lib" ascii wide nocase
$s4 = "win32/libsam" ascii wide nocase
condition:
uint16(0) == 0x5a4d and any of them
}Sigma Rule
title: Suspicious Libsam Activity
id: ce06634477a8bc4568ba6e23f812431f
status: experimental
description: Detects generic indicators of the libsam malware family.
logsource:
category: process_creation
product: windows
detection:
selection:
Image|endswith:
- '\cmd.exe'
- '\powershell.exe'
CommandLine|contains:
- "*libsam*"
- "*hacktool.libsam*"
- "*riskware.pwdump.lib*"
- "*win32/libsam*"
condition: selection
level: mediumReferences & External Analysis
- Search "libsam" on VirusTotal (External Analysis)
Frequently Asked Questions
How do I remove the Libsam Advanced_Threat from Windows?
Manual removal of Libsam is highly discouraged as it may leave persistence mechanisms intact. We recommend disconnecting the device from the internet and utilizing a professional incident response service or enterprise-grade EDR software to conduct a full forensic sweep.
Is Libsam a virus or a Advanced_Threat?
Libsam is classified as a Advanced_Threat. Unlike traditional viruses that infect files, modern malware like Libsam typically operates as a standalone payload designed to compromise systems, steal data, or deploy secondary stage implants.
What are the main symptoms of a Libsam infection?
Symptoms of Libsam can include unexpected system slowness, unauthorized outbound network traffic to unknown IP addresses, disabled security software, and suspicious background processes running from AppData or Temp directories.
Related Families (Category: advanced_threat)
Explore other malware families in the same category:
Protect Your Network Against Advanced_Threats
Want to prevent Libsam and similar threats from compromising your organization? Read our comprehensive defensive guide: Suspect an Infection? What to do.
Machine-readable
Get this profile as JSON: https://jordanricky1604-ship-it.github.io/malware-families-catalog/api/libsam.json
Ecosystem & Interactive Environments
This profile is part of the Malware Families Catalog, a public dataset of 2,899 malware families. The catalog is also published across our ecosystem: Hugging Face, Kaggle, Zenodo, Replit, StackBlitz, CodeSandbox, and CodePen.