Sigma Rules
1,701 rules found
Bypass UAC Using DelegateExecute
Bypasses User Account Control using a fileless method
Bypass UAC Using Event Viewer
Bypasses User Account Control using Event Viewer and a relevant Windows Registry modification
Bypass UAC Using SilentCleanup Task
Detects the setting of the environement variable "windir" to a non default value. Attackers often abuse this variable in order to trigger a UAC bypass via the "SilentCleanup" task. The SilentCleanup task located in %windir%\system32\cleanmgr.exe is an auto-elevated task that can be abused to elevate any file with administrator privileges without prompting UAC.
Default RDP Port Changed to Non Standard Port
Detects changes to the default RDP port. Remote desktop is a common feature in operating systems. It allows a user to log into a remote system using an interactive session with a graphical user interface. Microsoft refers to its implementation of the Remote Desktop Protocol (RDP) as Remote Desktop Services (RDS).
Sysmon Driver Altitude Change
Detects changes in Sysmon driver altitude value. If the Sysmon driver is configured to load at an altitude of another registered service, it will fail to load at boot.
Change Winevt Channel Access Permission Via Registry
Detects tampering with the "ChannelAccess" registry key in order to change access to Windows event channel.
Running Chrome VPN Extensions via the Registry 2 VPN Extension
Running Chrome VPN Extensions via the Registry install 2 vpn extension
Potential CobaltStrike Service Installations - Registry
Detects known malicious service installs that appear in cases in which a Cobalt Strike beacon elevates privileges or lateral movement.
COM Hijack via Sdclt
Detects changes to 'HKCU\Software\Classes\Folder\shell\open\command\DelegateExecute'
Security Event Logging Disabled via MiniNt Registry Key - Registry Set
Detects the addition of the 'MiniNt' key to the registry. Upon a reboot, Windows Event Log service will stop writing events. Windows Event Log is a service that collects and stores event logs from the operating system and applications. It is an important component of Windows security and auditing. Adversary may want to disable this service to disable logging of security events which could be used to detect their activities.
Service Binary in Suspicious Folder
Detect the creation of a service with a service binary located in a suspicious directory
Windows Credential Guard Disabled - Registry
Detects attempts to disable Windows Credential Guard by setting registry values to 0. Credential Guard uses virtualization-based security to isolate secrets so that only privileged system software can access them. Adversaries may disable Credential Guard to gain access to sensitive credentials stored in the system, such as NTLM hashes and Kerberos tickets, which can be used for lateral movement and privilege escalation.
Custom File Open Handler Executes PowerShell
Detects the abuse of custom file open handler, executing powershell
Antivirus Filter Driver Disallowed On Dev Drive - Registry
Detects activity that indicates a user disabling the ability for Antivirus mini filter to inspect a "Dev Drive".
Windows Hypervisor Enforced Code Integrity Disabled
Detects changes to the HypervisorEnforcedCodeIntegrity registry key and the "Enabled" value being set to 0 in order to disable the Hypervisor Enforced Code Integrity feature. This allows an attacker to load unsigned and untrusted code to be run in the kernel
Hypervisor Enforced Paging Translation Disabled
Detects changes to the "DisableHypervisorEnforcedPagingTranslation" registry value. Where the it is set to "1" in order to disable the Hypervisor Enforced Paging Translation feature.
DHCP Callout DLL Installation
Detects the installation of a Callout DLL via CalloutDlls and CalloutEnabled parameter in Registry, which can be used to execute code in context of the DHCP server (restart required)
Potential AutoLogger Sessions Tampering
Detects tampering with autologger trace sessions which is a technique used by attackers to disable logging
Disable Macro Runtime Scan Scope
Detects tampering with the MacroRuntimeScanScope registry key to disable runtime scanning of enabled macros
Registry Disable System Restore
Detects the modification of the registry to disable a system restore on the computer
Windows Defender Service Disabled - Registry
Detects when an attacker or tool disables the Windows Defender service (WinDefend) via the registry
Windows Event Log Access Tampering Via Registry
Detects changes to the Windows EventLog channel permission values. It focuses on changes to the Security Descriptor Definition Language (SDDL) string, as modifications to these values can restrict access to specific users or groups, potentially aiding in defense evasion by controlling who can view or modify a event log channel. Upon execution, the user shouldn't be able to access the event log channel via the event viewer or via utilities such as "Get-EventLog" or "wevtutil".
Disable Windows Event Logging Via Registry
Detects tampering with the "Enabled" registry key in order to disable Windows logging of a Windows event channel
Disabled Windows Defender Eventlog
Detects the disabling of the Windows Defender eventlog as seen in relation to Lockbit 3.0 infections
Disable PUA Protection on Windows Defender
Detects disabling Windows Defender PUA protection
New DNS ServerLevelPluginDll Installed
Detects the installation of a DNS plugin DLL via ServerLevelPluginDll parameter in registry, which can be used to execute code in context of the DNS server (restart required)
ETW Logging Disabled In .NET Processes - Sysmon Registry
Potential adversaries stopping ETW providers recording loaded .NET assemblies.
Directory Service Restore Mode(DSRM) Registry Value Tampering
Detects changes to "DsrmAdminLogonBehavior" registry value. During a Domain Controller (DC) promotion, administrators create a Directory Services Restore Mode (DSRM) local administrator account with a password that rarely changes. The DSRM account is an “Administrator” account that logs in with the DSRM mode when the server is booting up to restore AD backups or recover the server from a failure. Attackers could abuse DSRM account to maintain their persistence and access to the organization's Active Directory. If the "DsrmAdminLogonBehavior" value is set to "0", the administrator account can only be used if the DC starts in DSRM. If the "DsrmAdminLogonBehavior" value is set to "1", the administrator account can only be used if the local AD DS service is stopped. If the "DsrmAdminLogonBehavior" value is set to "2", the administrator account can always be used.
Potential EventLog File Location Tampering
Detects tampering with EventLog service "file" key. In order to change the default location of an Evtx file. This technique is used to tamper with log collection and alerting
Suspicious Application Allowed Through Exploit Guard
Detects applications being added to the "allowed applications" list of exploit guard in order to bypass controlled folder settings
Change User Account Associated with the FAX Service
Detect change of the user account associated with the FAX service to avoid the escalation problem.
Change the Fax Dll
Detect possible persistence using Fax DLL load when service restart
New File Association Using Exefile
Detects the abuse of the exefile handler in new file association. Used for bypass of security products.
FileFix - Command Evidence in TypedPaths
Detects commonly-used chained commands and strings in the most recent 'url' value of the 'TypedPaths' key, which could be indicative of a user being targeted by the FileFix technique.
Add Debugger Entry To Hangs Key For Persistence
Detects when an attacker adds a new "Debugger" value to the "Hangs" key in order to achieve persistence which will get invoked when an application crashes
Persistence Via Hhctrl.ocx
Detects when an attacker modifies the registry value of the "hhctrl" to point to a custom binary
Hide Schedule Task Via Index Value Tamper
Detects when the "index" value of a scheduled task is modified from the registry Which effectively hides it from any tooling such as "schtasks /query" (Read the referenced link for more information about the effects of this technique)
Driver Added To Disallowed Images In HVCI - Registry
Detects changes to the "HVCIDisallowedImages" registry value to potentially add a driver to the list, in order to prevent it from loading.
IE ZoneMap Setting Downgraded To MyComputer Zone For HTTP Protocols
Detects changes to Internet Explorer's (IE / Windows Internet properties) ZoneMap configuration of the "HTTP" and "HTTPS" protocols to point to the "My Computer" zone. This allows downloaded files from the Internet to be granted the same level of trust as files stored locally.
Uncommon Extension In Keyboard Layout IME File Registry Value
Detects usage of Windows Input Method Editor (IME) keyboard layout feature, which allows an attacker to load a DLL into the process after sending the WM_INPUTLANGCHANGEREQUEST message. Before doing this, the client needs to register the DLL in a special registry key that is assumed to implement this keyboard layout. This registry key should store a value named "Ime File" with a DLL path. IMEs are essential for languages that have more characters than can be represented on a standard keyboard, such as Chinese, Japanese, and Korean.
Suspicious Path In Keyboard Layout IME File Registry Value
Detects usage of Windows Input Method Editor (IME) keyboard layout feature, which allows an attacker to load a DLL into the process after sending the WM_INPUTLANGCHANGEREQUEST message. Before doing this, the client needs to register the DLL in a special registry key that is assumed to implement this keyboard layout. This registry key should store a value named "Ime File" with a DLL path. IMEs are essential for languages that have more characters than can be represented on a standard keyboard, such as Chinese, Japanese, and Korean.
Potential Ransomware Activity Using LegalNotice Message
Detect changes to the "LegalNoticeCaption" or "LegalNoticeText" registry values where the message set contains keywords often used in ransomware ransom messages
Lolbas OneDriveStandaloneUpdater.exe Proxy Download
Detects setting a custom URL for OneDriveStandaloneUpdater.exe to download a file from the Internet without executing any anomalous executables with suspicious arguments. The downloaded file will be in C:\Users\redacted\AppData\Local\Microsoft\OneDrive\StandaloneUpdaterreSignInSettingsConfig.json
RestrictedAdminMode Registry Value Tampering
Detects changes to the "DisableRestrictedAdmin" registry value in order to disable or enable RestrictedAdmin mode. RestrictedAdmin mode prevents the transmission of reusable credentials to the remote system to which you connect using Remote Desktop. This prevents your credentials from being harvested during the initial connection process if the remote server has been compromise
Lsass Full Dump Request Via DumpType Registry Settings
Detects the setting of the "DumpType" registry value to "2" which stands for a "Full Dump". Technique such as LSASS Shtinkering requires this value to be "2" in order to dump LSASS.
NET NGenAssemblyUsageLog Registry Key Tamper
Detects changes to the NGenAssemblyUsageLog registry key. .NET Usage Log output location can be controlled by setting the NGenAssemblyUsageLog CLR configuration knob in the Registry or by configuring an environment variable (as described in the next section). By simplify specifying an arbitrary value (e.g. fake output location or junk data) for the expected value, a Usage Log file for the .NET execution context will not be created.
New Netsh Helper DLL Registered From A Suspicious Location
Detects changes to the Netsh registry key to add a new DLL value that is located on a suspicious location. This change might be an indication of a potential persistence attempt by adding a malicious Netsh helper
Potentially Suspicious ODBC Driver Registered
Detects the registration of a new ODBC driver where the driver is located in a potentially suspicious location