Sigma Rules
1,607 rules found
DLL Sideloading by VMware Xfer Utility
Detects execution of VMware Xfer utility (VMwareXferlogs.exe) from the non-default directory which may be an attempt to sideload arbitrary DLL
Dllhost.EXE Execution Anomaly
Detects a "dllhost" process spawning with no commandline arguments which is very rare to happen and could indicate process injection activity or malware mimicking similar system processes.
DNS Exfiltration and Tunneling Tools Execution
Well-known DNS Exfiltration tools execution
Unusual Child Process of dns.exe
Detects an unexpected process spawning from dns.exe which may indicate activity related to remote code execution or other forms of exploitation as seen in CVE-2020-1350 (SigRed)
Potential Discovery Activity Via Dnscmd.EXE
Detects an attempt to leverage dnscmd.exe to enumerate the DNS zones of a domain. DNS zones used to host the DNS records for a particular domain.
New DNS ServerLevelPluginDll Installed Via Dnscmd.EXE
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)
Potential Application Whitelisting Bypass via Dnx.EXE
Detects the execution of Dnx.EXE. The Dnx utility allows for the execution of C# code. Attackers might abuse this in order to bypass application whitelisting.
Arbitrary DLL or Csproj Code Execution Via Dotnet.EXE
Detects execution of arbitrary DLLs or unsigned code via a ".csproj" files via Dotnet.EXE.
Binary Proxy Execution Via Dotnet-Trace.EXE
Detects commandline arguments for executing a child process via dotnet-trace.exe
Process Memory Dump Via Dotnet-Dump
Detects the execution of "dotnet-dump" with the "collect" flag. The execution could indicate potential process dumping of critical processes such as LSASS.
Potential Recon Activity Using DriverQuery.EXE
Detect usage of the "driverquery" utility to perform reconnaissance on installed drivers
DriverQuery.EXE Execution
Detect usage of the "driverquery" utility. Which can be used to perform reconnaissance on installed drivers
Potentially Over Permissive Permissions Granted Using Dsacls.EXE
Detects usage of Dsacls to grant over permissive permissions
Potential Password Spraying Attempt Using Dsacls.EXE
Detects possible password spraying attempts using Dsacls
Domain Trust Discovery Via Dsquery
Detects execution of "dsquery.exe" for domain trust discovery
Suspicious Kernel Dump Using Dtrace
Detects suspicious way to dump the kernel on Windows systems using dtrace.exe, which is available on Windows systems since Windows 10 19H1
Potential Windows Defender AV Bypass Via Dump64.EXE Rename
Detects when a user is potentially trying to bypass the Windows Defender AV by renaming a tool to dump64.exe and placing it in the Visual Studio folder. Currently the rule is covering only usage of procdump but other utilities can be added in order to increase coverage.
DumpMinitool Execution
Detects the use of "DumpMinitool.exe" a tool that allows the dump of process memory via the use of the "MiniDumpWriteDump"
Suspicious DumpMinitool Execution
Detects suspicious ways to use the "DumpMinitool.exe" binary
New Capture Session Launched Via DXCap.EXE
Detects the execution of "DXCap.EXE" with the "-c" flag, which allows a user to launch any arbitrary binary or windows package through DXCap itself. This can be abused to potentially bypass application whitelisting.
Esentutl Gather Credentials
Conti recommendation to its affiliates to use esentutl to access NTDS dumped file. Trickbot also uses this utilities to get MSEdge info via its module pwgrab.
Copying Sensitive Files with Credential Data
Files with well-known filenames (sensitive files with credential data) copying
Esentutl Steals Browser Information
One way Qbot steals sensitive information is by extracting browser data from Internet Explorer and Microsoft Edge by using the built-in utility esentutl.exe
Security Event Logging Disabled via MiniNt Registry Key - Process
Detects attempts to disable security event logging by adding the `MiniNt` registry key. This key is used to disable the Windows Event Log service, which collects and stores event logs from the operating system and applications. Adversaries may want to disable this service to prevent logging of security events that could be used to detect their activities.
Potentially Suspicious Event Viewer Child Process
Detects uncommon or suspicious child processes of "eventvwr.exe" which might indicate a UAC bypass attempt
Potentially Suspicious Cabinet File Expansion
Detects the expansion or decompression of cabinet files from potentially suspicious or uncommon locations, e.g. seen in Iranian MeteorExpress related attacks
Explorer Process Tree Break
Detects a command line process that uses explorer.exe to launch arbitrary commands or binaries, which is similar to cmd.exe /c, only it breaks the process tree and makes its parent a new instance of explorer spawning from "svchost"
File Explorer Folder Opened Using Explorer Folder Shortcut Via Shell
Detects the initial execution of "cmd.exe" which spawns "explorer.exe" with the appropriate command line arguments for opening the "My Computer" folder.
Explorer NOUACCHECK Flag
Detects suspicious starts of explorer.exe that use the /NOUACCHECK flag that allows to run all sub processes of that newly started explorer.exe without any UAC checks
Remote File Download Via Findstr.EXE
Detects execution of "findstr" with specific flags and a remote share path. This specific set of CLI flags would allow "findstr" to download the content of the file located on the remote share as described in the LOLBAS entry.
Findstr GPP Passwords
Look for the encrypted cpassword value within Group Policy Preference files on the Domain Controller. This value can be decrypted with gpp-decrypt.
Findstr Launching .lnk File
Detects usage of findstr to identify and execute a lnk file as seen within the HHS redirect attack
LSASS Process Reconnaissance Via Findstr.EXE
Detects findstring commands that include the keyword lsass, which indicates recon actviity for the LSASS process PID
Permission Misconfiguration Reconnaissance Via Findstr.EXE
Detects usage of findstr with the "EVERYONE" or "BUILTIN" keywords. This was seen being used in combination with "icacls" and other utilities to spot misconfigured files or folders permissions.
Recon Command Output Piped To Findstr.EXE
Detects the execution of a potential recon command where the results are piped to "findstr". This is meant to trigger on inline calls of "cmd.exe" via the "/c" or "/k" for example. Attackers often time use this technique to extract specific information they require in their reconnaissance phase.
Security Tools Keyword Lookup Via Findstr.EXE
Detects execution of "findstr" to search for common names of security tools. Attackers often pipe the results of recon commands such as "tasklist" or "whoami" to "findstr" in order to filter out the results. This detection focuses on the keywords that the attacker might use as a filter.
Insensitive Subfolder Search Via Findstr.EXE
Detects execution of findstr with the "s" and "i" flags for a "subfolder" and "insensitive" search respectively. Attackers sometimes leverage this built-in utility to search the system for interesting files or filter through results of commands.
Sysmon Discovery Via Default Driver Altitude Using Findstr.EXE
Detects usage of "findstr" with the argument "385201". Which could indicate potential discovery of an installed Sysinternals Sysmon service using the default driver altitude (even if the name is changed).
Finger.EXE Execution
Detects execution of the "finger.exe" utility. Finger.EXE or "TCPIP Finger Command" is an old utility that is still present on modern Windows installation. It Displays information about users on a specified remote computer (typically a UNIX computer) that is running the finger service or daemon. Due to the old nature of this utility and the rareness of machines having the finger service. Any execution of "finger.exe" can be considered "suspicious" and worth investigating.
Filter Driver Unloaded Via Fltmc.EXE
Detect filter driver unloading activity via fltmc.exe
Sysmon Driver Unloaded Via Fltmc.EXE
Detects possible Sysmon filter driver unloaded via fltmc.exe
Forfiles.EXE Child Process Masquerading
Detects the execution of "forfiles" from a non-default location, in order to potentially spawn a custom "cmd.exe" from the current working directory.
Forfiles Command Execution
Detects the execution of "forfiles" with the "/c" flag. While this is an expected behavior of the tool, it can be abused in order to proxy execution through it with any binary. Can be used to bypass application whitelisting.
Uncommon FileSystem Load Attempt By Format.com
Detects the execution of format.com with an uncommon filesystem selection that could indicate a defense evasion activity in which "format.com" is used to load malicious DLL files or other programs.
Use of FSharp Interpreters
Detects the execution of FSharp Interpreters "FsiAnyCpu.exe" and "FSi.exe" Both can be used for AWL bypass and to execute F# code via scripts or inline.
Fsutil Drive Enumeration
Attackers may leverage fsutil to enumerated connected drives.
Potentially Suspicious NTFS Symlink Behavior Modification
Detects the modification of NTFS symbolic link behavior using fsutil, which could be used to enable remote to local or remote to remote symlinks for potential attacks.
Fsutil Suspicious Invocation
Detects suspicious parameters of fsutil (deleting USN journal, configuring it with small size, etc). Might be used by ransomwares during the attack (seen by NotPetya and others).