Sigma Rules
921 rules found for "Microsoft"
Import New Module Via PowerShell CommandLine
Detects usage of the "Import-Module" cmdlet in order to add new Cmdlets to the current PowerShell session
Regsvr32.EXE Calling of DllRegisterServer Export Function Implicitly
Detects execution of regsvr32 with the silent flag and no other flags on a DLL located in an uncommon or potentially suspicious location. When Regsvr32 is called in such a way, it implicitly calls the DLL export function 'DllRegisterServer'.
Rundll32.EXE Calling DllRegisterServer Export Function Explicitly
Detects when the DLL export function 'DllRegisterServer' is called in the commandline by Rundll32 explicitly where the DLL is located in a non-standard path.
EventLog Query Requests By Builtin Utilities
Detect attempts to query the contents of the event log using command line utilities. Attackers use this technique in order to look for sensitive information in the logs such as passwords, usernames, IPs, etc.
Tunneling Tool Execution
Detects the execution of well known tools that can be abused for data exfiltration and tunneling.
File or Folder Permissions Modifications
Detects a file or folder's permissions being modified or tampered with.
Use Short Name Path in Command Line
Detects the use of short name paths (8.3 format) in command lines, which can be used to obfuscate paths or access restricted locations. Windows creates short 8.3 filenames (like PROGRA~1) for compatibility with MS-DOS-based or 16-bit Windows programs. When investigating, examine: - Commands using short paths to access sensitive directories or files - Web servers on Windows (especially Apache) where short filenames could bypass security controls - Correlation with other suspicious behaviors - baseline of short name usage in your environment and look for deviations
Microsoft Office Trusted Location Updated
Detects changes to the registry keys related to "Trusted Location" of Microsoft Office. Attackers might add additional trusted locations to avoid macro security restrictions.
Registry Set With Crypto-Classes From The "Cryptography" PowerShell Namespace
Detects the setting of a registry inside the "\Shell\Open\Command" value with PowerShell classes from the "System.Security.Cryptography" namespace. The PowerShell namespace "System.Security.Cryptography" provides classes for on-the-fly encryption and decryption. These can be used for example in decrypting malicious payload for defense evasion.