Sigma detection rules, expert-reviewed

Windows System Time Discovery via net.exe or w32tm.exe

Flags Windows net.exe/net1.exe or w32tm.exe command lines used to query system time/time zone.

Windows hh.exe Execution Triggered by .chm Command Line

Flags hh.exe being executed with a command line referencing a .chm file on Windows.

Windows Security 4697: TAP Driver Service Installation (tap0901)

Alerts on Windows Security EID 4697 service installation events for TAP driver files containing "tap0901."

Linux auditd: dd overwrites a file using /dev/null or /dev/zero

Flags dd command lines that overwrite files by sourcing data from /dev/null or /dev/zero.

Windows Raw Disk Access by Uncommon Process Paths

Alerts on Windows raw disk access by processes from uncommon or suspicious locations.

Windows Local Account Discovery via System Utilities Process Execution

Flags Windows processes that match utilities used to enumerate local user and account information.

Windows Rar.exe Files Added to Archive Activity

Alerts when Windows rar.exe is used to add files to an archive using the " a " command-line pattern.

Windows: net.exe used to start a service with the start flag

Identifies Windows processes using net.exe/net1.exe with ' start ' to start services.

Windows Process: File Association Changes via assoc Command

Alerts on cmd.exe launches running the assoc command to modify Windows default file associations.

Linux System Owner or User Discovery via Common Utility Execution

Flags execution of Linux user/system identification utilities such as whoami and id.

Linux: Detect execution of tcpdump or tshark with interface (-i) capture option

Alerts on tcpdump or tshark executions on Linux where an interface flag is present, consistent with network sniffing.

Linux Auditd: Command Execution of zip, gzip -k, or tar -c for Data Compression

Alerts on Linux execve events launching zip, gzip (-k), or tar create commands often used to compress data.

PowerShell Compress-Archive Cmdlet Execution for Data Compression

Flags PowerShell scripts using the Compress-Archive cmdlet, consistent with local data packaging before collection or exfiltration.

Linux Service Reload/Start via systemctl or service Command Execution

Identifies Linux process executions invoking service control commands with start or reload keywords.

Linux auditd: chmod/chown process execution indicating file or folder permission changes

Flags Linux EXECVE events running chmod or chown, which commonly correspond to file/folder permission changes.