Dumpert Process Memory Dumping Tool Activity

Dumpert is a Windows-based hacktool designed to perform memory dumping of the Local Security Authority Subsystem Service (lsass.exe). By extracting memory from this process, attackers aim to harvest sensitive credentials, including NTLM hashes and plaintext passwords, which are essential for lateral movement and privilege escalation within a Windows environment. The tool is known for implementing custom techniques to evade standard detection methods used by security software that monitors direct calls to memory dumping APIs. Monitoring for the execution of Dumpert is critical, as it signifies an active attempt by an adversary to perform credential access at the endpoint level, typically during the post-exploitation phase of an intrusion.

Attack Chain

1. Attacker gains initial access to the target Windows system.
2. Attacker performs local enumeration to identify the process ID of lsass.exe.
3. Attacker drops the Dumpert executable or DLL onto the target file system.
4. Attacker executes Dumpert.exe or invokes Dumpert.dll via command line.
5. The tool utilizes direct system calls or custom API implementations to bypass common EDR hooks.
6. The memory contents of lsass.exe are read and written to a local dump file on disk.
7. The attacker exfiltrates the resulting memory dump file to an external command-and-control server.
8. Credentials are extracted offline using tools like Mimikatz to escalate privileges or move laterally.

Impact

Successful execution of Dumpert provides adversaries with high-value credentials, enabling full account compromise, domain escalation, and long-term persistent access to the network. This activity is a precursor to large-scale data exfiltration and potential ransomware deployment.

Recommendation

• Deploy the provided Sigma rule to detect the execution of the Dumpert binary or the loading of its associated DLL.
• Enable Sysmon process-creation logging (Event ID 1) to capture command line arguments and file hashes required for rule execution.
• Implement strict endpoint controls to restrict the execution of unauthorized binaries in temporary directories where such tools are commonly staged.
• Monitor for unexpected access to lsass.exe memory space by non-system processes.