Adversaries may register malicious network provider dynamic link libraries (DLLs) to capture cleartext user credentials during the authentication process. Network provider DLLs allow Windows to interface with specific network protocols and can also support add-on credential management functions.(Citation: Network Provider API) During the logon process, Winlogon (the interactive logon module) sends credentials to the local mpnotify.exe
process via RPC. The mpnotify.exe
process then shares the credentials in cleartext with registered credential managers when notifying that a logon event is happening.(Citation: NPPSPY - Huntress)(Citation: NPPSPY Video)(Citation: NPLogonNotify)
Adversaries can configure a malicious network provider DLL to receive credentials from mpnotify.exe
.(Citation: NPPSPY) Once installed as a credential manager (via the Registry), a malicious DLL can receive and save credentials each time a user logs onto a Windows workstation or domain via the NPLogonNotify()
function.(Citation: NPLogonNotify)
Adversaries may target planting malicious network provider DLLs on systems known to have increased logon activity and/or administrator logon activity, such as servers and domain controllers.(Citation: NPPSPY - Huntress)
View in MITRE ATT&CK®Capability ID | Capability Description | Mapping Type | ATT&CK ID | ATT&CK Name |
---|---|---|---|---|
SI-07 | Software, Firmware, and Information Integrity | Protects | T1556.008 | Network Provider DLL |
CM-03 | Configuration Change Control | Protects | T1556.008 | Network Provider DLL |
CM-07 | Least Functionality | Protects | T1556.008 | Network Provider DLL |
CM-06 | Configuration Settings | Protects | T1556.008 | Network Provider DLL |
CM-05 | Access Restrictions for Change | Protects | T1556.008 | Network Provider DLL |
AC-06 | Least Privilege | Protects | T1556.008 | Network Provider DLL |
CM-02 | Baseline Configuration | Protects | T1556.008 | Network Provider DLL |
SI-04 | System Monitoring | Protects | T1556.008 | Network Provider DLL |
AC-03 | Access Enforcement | Protects | T1556.008 | Network Provider DLL |