Adversaries may rely on a targeted organizations user interaction for the execution of malicious code. User interaction may consist of installing applications, opening email attachments, or granting higher permissions to documents.
Adversaries may embed malicious code or visual basic code into files such as Microsoft Word and Excel documents or software installers. [1] Execution of this code requires that the user enable scripting or write access within the document. Embedded code may not always be noticeable to the user especially in cases of trojanized software. [2]
A Chinese spearphishing campaign running from December 9, 2011 through February 29, 2012 delivered malware through spearphishing attachments which required user action to achieve execution. [3]
| ID | Name | Description |
|---|---|---|
| S0093 | Backdoor.Oldrea |
Execution of Backdoor.Oldrea relies on a user opening a trojanized installer attached to an email. [2] [4] |
| S0606 | Bad Rabbit |
Bad Rabbit is disguised as an Adobe Flash installer. When the file is opened it starts locking the infected computer. [5] |
| S0496 | REvil |
REvil initially executes when the user clicks on a JavaScript file included in the phishing emails .zip attachment. [6] |
| S0603 | Stuxnet |
Stuxnet infects DLL's associated with the WinCC Simatic manager which are responsible for opening project files. If a user opens an uninfected project file using a compromised manager, the file will be infected with Stuxnet code. If an infected project is opened with the Simatic manager, the modified data file will trigger a search for the |
| ID | Asset |
|---|---|
| A0002 | Human-Machine Interface (HMI) |
| A0012 | Jump Host |
| A0001 | Workstation |
| ID | Mitigation | Description |
|---|---|---|
| M0949 | Antivirus/Antimalware |
Ensure anti-virus solution can detect malicious files that allow user execution (e.g., Microsoft Office Macros, program installers). |
| M0945 | Code Signing |
Prevent the use of unsigned executables, such as installers and scripts. |
| M0938 | Execution Prevention |
Application control may be able to prevent the running of executables masquerading as other files. |
| M0931 | Network Intrusion Prevention |
If a link is being visited by a user, network intrusion prevention systems and systems designed to scan and remove malicious downloads can be used to block activity. |
| M0921 | Restrict Web-Based Content |
If a link is being visited by a user, block unknown or unused files in transit by default that should not be downloaded or by policy from suspicious sites as a best practice to prevent some vectors, such as .scr, .exe, .pif, .cpl, etc. Some download scanning devices can open and analyze compressed and encrypted formats, such as zip and rar that may be used to conceal malicious files. |
| M0917 | User Training |
Use user training as a way to bring awareness to common phishing and spearphishing techniques and how to raise suspicion for potentially malicious events. |
| ID | Name | Analytic ID | Analytic Description |
|---|---|---|---|
| DET0791 | Detection of User Execution | AN1923 |
Real-time monitoring identifies a user-invoked action on an Industrial Control System (ICS) workstation immediately followed by a process execution chain inconsistent with normal ICS operations -- the user-driven trigger plus the resulting anomalous execution chain together distinguish this from generic malware execution. OT operational-fidelity gate: Alert only when the account/device/session violates the approved identity + source host/jump path/zone policy and is corroborated by access to a protected OT asset, execution, configuration change, or another security-relevant follow-on event. Suppress approved shift activity, vendor support, break-glass use, commissioning, and documented remote-access windows. |
| AN2150 |
Real-time monitoring identifies a user-facing application on an ICS Linux workstation spawning a child process outside the expected application-child baseline. OT operational-fidelity gate: Alert only when the account/device/session violates the approved identity + source host/jump path/zone policy and is corroborated by access to a protected OT asset, execution, configuration change, or another security-relevant follow-on event. Suppress approved shift activity, vendor support, break-glass use, commissioning, and documented remote-access windows. |
||
| AN2220 |
Real-time monitoring identifies an Industrial Control System (ICS) embedded device executing a sequence of operations inconsistent with its programmed logic, correlating temporally with an operator interaction on an engineering terminal connected to the device. OT operational-fidelity gate: Alert only when the account/device/session violates the approved identity + source host/jump path/zone policy and is corroborated by access to a protected OT asset, execution, configuration change, or another security-relevant follow-on event. Suppress approved shift activity, vendor support, break-glass use, commissioning, and documented remote-access windows. |