Rule Library

Sigma Rules

1,473 rules found

3,707Total
3,116Detection
451Emerging
137Hunting
Detectionmediumtest

Google Workspace Role Privilege Deleted

Detects when an a role privilege is deleted in Google Workspace.

Google Cloudgoogle_workspace.admin
TA0040 · Impact
Austin SongerTue Aug 24cloud
Detectionmediumtest

Google Workspace User Granted Admin Privileges

Detects when an Google Workspace user is granted admin privileges.

Google Cloudgoogle_workspace.admin
TA0004 · Privilege EscalationTA0003 · PersistenceT1098 · Account Manipulation
Austin SongerMon Aug 23cloud
Detectionmediumtest

New Federated Domain Added

Detects the addition of a new Federated Domain.

Microsoft 365audit
TA0005 · Defense EvasionTA0004 · Privilege EscalationT1484.002 · Trust Modification
Splunk Threat Research Team (original rule)+1Mon Sep 18cloud
Detectionmediumtest

New Federated Domain Added - Exchange

Detects the addition of a new Federated Domain.

Microsoft 365exchange
TA0003 · PersistenceT1136.003 · Cloud Account
Splunk Threat Research Team (original rule)+1Tue Feb 08cloud
Detectionmediumtest

Activity from Suspicious IP Addresses

Detects when a Microsoft Cloud App Security reported users were active from an IP address identified as risky by Microsoft Threat Intelligence. These IP addresses are involved in malicious activities, such as Botnet C&C, and may indicate compromised account.

Microsoft 365threat_detection
TA0011 · Command and ControlT1573 · Encrypted Channel
Austin SongerMon Aug 23cloud
Detectionmediumtest

Activity Performed by Terminated User

Detects when a Microsoft Cloud App Security reported for users whose account were terminated in Azure AD, but still perform activities in other platforms such as AWS or Salesforce. This is especially relevant for users who use another account to manage resources, since these accounts are often not terminated when a user leaves the company.

Microsoft 365threat_management
TA0040 · Impact
Austin SongerMon Aug 23cloud
Detectionmediumtest

Activity from Anonymous IP Addresses

Detects when a Microsoft Cloud App Security reported when users were active from an IP address that has been identified as an anonymous proxy IP address.

Microsoft 365threat_management
TA0011 · Command and ControlT1573 · Encrypted Channel
Austin SongerMon Aug 23cloud
Detectionmediumtest

Activity from Infrequent Country

Detects when a Microsoft Cloud App Security reported when an activity occurs from a location that wasn't recently or never visited by any user in the organization.

Microsoft 365threat_management
TA0011 · Command and ControlT1573 · Encrypted Channel
Austin SongerMon Aug 23cloud
Detectionmediumtest

Data Exfiltration to Unsanctioned Apps

Detects when a Microsoft Cloud App Security reported when a user or IP address uses an app that is not sanctioned to perform an activity that resembles an attempt to exfiltrate information from your organization.

Microsoft 365threat_management
TA0010 · ExfiltrationT1537 · Transfer Data to Cloud Account
Austin SongerMon Aug 23cloud
Detectionmediumtest

Microsoft 365 - Impossible Travel Activity

Detects when a Microsoft Cloud App Security reported a risky sign-in attempt due to a login associated with an impossible travel.

Microsoft 365threat_management
TA0004 · Privilege EscalationTA0003 · PersistenceTA0005 · Defense EvasionTA0001 · Initial Access+1
Austin SongerMon Jul 06cloud
Detectionmediumtest

Logon from a Risky IP Address

Detects when a Microsoft Cloud App Security reported when a user signs into your sanctioned apps from a risky IP address.

Microsoft 365threat_management
TA0004 · Privilege EscalationTA0003 · PersistenceTA0005 · Defense EvasionTA0001 · Initial Access+1
Austin SongerMon Aug 23cloud
Detectionmediumtest

Microsoft 365 - Potential Ransomware Activity

Detects when a Microsoft Cloud App Security reported when a user uploads files to the cloud that might be infected with ransomware.

Microsoft 365threat_management
TA0040 · ImpactT1486 · Data Encrypted for Impact
Austin SongerThu Aug 19cloud
Detectionmediumtest

PST Export Alert Using eDiscovery Alert

Alert on when a user has performed an eDiscovery search or exported a PST file from the search. This PST file usually has sensitive information including email body content

Microsoft 365threat_management
TA0009 · CollectionT1114 · Email Collection
Sorina IonescuTue Feb 08cloud
Detectionmediumtest

PST Export Alert Using New-ComplianceSearchAction

Alert when a user has performed an export to a search using 'New-ComplianceSearchAction' with the '-Export' flag. This detection will detect PST export even if the 'eDiscovery search or exported' alert is disabled in the O365.This rule will apply to ExchangePowerShell usage and from the cloud.

Microsoft 365threat_management
TA0009 · CollectionT1114 · Email Collection
Nikita KhalimonenkovThu Nov 17cloud
Detectionmediumtest

Suspicious OAuth App File Download Activities

Detects when a Microsoft Cloud App Security reported when an app downloads multiple files from Microsoft SharePoint or Microsoft OneDrive in a manner that is unusual for the user.

Microsoft 365threat_management
TA0010 · Exfiltration
Austin SongerMon Aug 23cloud
Detectionmediumtest

Microsoft 365 - Unusual Volume of File Deletion

Detects when a Microsoft Cloud App Security reported a user has deleted a unusual a large volume of files.

Microsoft 365threat_management
TA0040 · ImpactT1485 · Data Destruction
Austin SongerThu Aug 19cloud
Detectionmediumtest

Microsoft 365 - User Restricted from Sending Email

Detects when a Security Compliance Center reported a user who exceeded sending limits of the service policies and because of this has been restricted from sending email.

Microsoft 365threat_management
TA0001 · Initial AccessT1199 · Trusted Relationship
Austin SongerThu Aug 19cloud
Detectionmediumtest

Cisco Duo Successful MFA Authentication Via Bypass Code

Detects when a successful MFA authentication occurs due to the use of a bypass code. A bypass code is a temporary passcode created by an administrator for a specific user to access a Duo-protected application. These are generally used as "backup codes," so that enrolled users who are having problems with their mobile devices (e.g., mobile service is disrupted, the device is lost or stolen, etc.) or who temporarily can't use their enrolled devices (on a plane without mobile data services) can still access their Duo-protected systems.

Ciscoduo
TA0006 · Credential AccessTA0005 · Defense EvasionTA0001 · Initial Access
Nikita KhalimonenkovWed Apr 17identity
Detectionmediumtest

Okta Admin Functions Access Through Proxy

Detects access to Okta admin functions through proxy.

Oktaokta
TA0006 · Credential Access
Muhammad FaisalWed Oct 25identity
Detectionmediumtest

Okta Admin Role Assigned to an User or Group

Detects when an the Administrator role is assigned to an user or group.

Oktaokta
TA0004 · Privilege EscalationTA0003 · PersistenceT1098.003 · Additional Cloud Roles
Austin SongerSun Sep 12identity
Detectionmediumtest

Okta Admin Role Assignment Created

Detects when a new admin role assignment is created. Which could be a sign of privilege escalation or persistence

Oktaokta
TA0003 · Persistence
Nikita KhalimonenkovThu Jan 19identity
Detectionmediumtest

Okta API Token Created

Detects when a API token is created

Oktaokta
TA0003 · Persistence
Austin SongerSun Sep 12identity
Detectionmediumtest

Okta API Token Revoked

Detects when a API Token is revoked.

Oktaokta
TA0040 · Impact
Austin SongerSun Sep 12identity
Detectionmediumtest

Okta Application Modified or Deleted

Detects when an application is modified or deleted.

Oktaokta
TA0040 · Impact
Austin SongerSun Sep 12identity
Detectionmediumtest

Okta Application Sign-On Policy Modified or Deleted

Detects when an application Sign-on Policy is modified or deleted.

Oktaokta
TA0040 · Impact
Austin SongerSun Sep 12identity
Detectionmediumtest

Okta Identity Provider Created

Detects when a new identity provider is created for Okta.

Oktaokta
TA0004 · Privilege EscalationTA0003 · PersistenceT1098.001 · Additional Cloud Credentials
kelnageThu Sep 07identity
Detectionmediumtest

Okta MFA Reset or Deactivated

Detects when an attempt at deactivating or resetting MFA.

Oktaokta
TA0003 · PersistenceTA0006 · Credential AccessTA0005 · Defense EvasionT1556.006 · Multi-Factor Authentication
Austin SongerTue Sep 21identity
Detectionmediumtest

Okta Network Zone Deactivated or Deleted

Detects when an Network Zone is Deactivated or Deleted.

Oktaokta
TA0040 · Impact
Austin SongerSun Sep 12identity
Detectionmediumtest

Okta Policy Rule Modified or Deleted

Detects when an Policy Rule is Modified or Deleted.

Oktaokta
TA0040 · Impact
Austin SongerSun Sep 12identity
Detectionmediumtest

Okta Security Threat Detected

Detects when an security threat is detected in Okta.

Oktaokta
TA0011 · Command and Control
Austin SongerSun Sep 12identity
Detectionmediumtest

Okta Unauthorized Access to App

Detects when unauthorized access to app occurs.

Oktaokta
TA0040 · Impact
Austin SongerSun Sep 12identity
Detectionmediumtest

Okta User Account Locked Out

Detects when an user account is locked out.

Oktaokta
TA0040 · ImpactT1531 · Account Access Removal
Austin SongerSun Sep 12identity
Detectionmediumtest

Bpfdoor TCP Ports Redirect

All TCP traffic on particular port from attacker is routed to different port. ex. '/sbin/iptables -t nat -D PREROUTING -p tcp -s 192.168.1.1 --dport 22 -j REDIRECT --to-ports 42392' The traffic looks like encrypted SSH communications going to TCP port 22, but in reality is being directed to the shell port once it hits the iptables rule for the attacker host only.

Linuxauditd
TA0005 · Defense EvasionT1562.004 · Disable or Modify System Firewall
Rafal PiaseckiWed Aug 10linux
Detectionmediumtest

File Time Attribute Change - Linux

Detect file time attribute change to hide new or changes to existing files.

Linuxauditd
TA0005 · Defense EvasionT1070.006 · Timestomp
Igor Fits+1Thu Oct 15linux
Detectionmediumtest

Remove Immutable File Attribute - Auditd

Detects removing immutable file attribute.

Linuxauditd
TA0005 · Defense Evasionattack.t1222.002
Jakob Weinzettl+1Mon Sep 23linux
Detectionmediumtest

Data Exfiltration with Wget

Detects attempts to post the file with the usage of wget utility. The adversary can bypass the permission restriction with the misconfigured sudo permission for wget utility which could allow them to read files like /etc/shadow.

Linuxauditd
TA0010 · ExfiltrationT1048.003 · Exfiltration Over Unencrypted Non-C2 Protocol
Pawel MazurThu Nov 18linux
Detectionmediumtest

Masquerading as Linux Crond Process

Masquerading occurs when the name or location of an executable, legitimate or malicious, is manipulated or abused for the sake of evading defenses and observation. Several different variations of this technique have been observed.

Linuxauditd
TA0005 · Defense EvasionT1036.003 · Rename System Utilities
Timur Zinniatullin+1Mon Oct 21linux
Detectionmediumtest

Modify System Firewall

Detects the removal of system firewall rules. Adversaries may only delete or modify a specific system firewall rule to bypass controls limiting network usage or access. Detection rules that match only on the disabling of firewalls will miss this.

Linuxauditd
T1562.004 · Disable or Modify System FirewallTA0005 · Defense Evasion
IAIMon Mar 06linux
Detectionmediumtest

Suspicious Commands Linux

Detects relevant commands often related to malware or hacking activity

Linuxauditd
TA0002 · ExecutionT1059.004 · Unix Shell
Florian Roth (Nextron Systems)Tue Dec 12linux
Detectionmediumtest

Suspicious History File Operations - Linux

Detects commandline operations on shell history files

Linuxauditd
TA0006 · Credential AccessT1552.003 · Bash History
Mikhail Larin+1Sat Oct 17linux
Detectionmediumtest

Suspicious C2 Activities

Detects suspicious activities as declared by Florian Roth in its 'Best Practice Auditd Configuration'. This includes the detection of the following commands; wget, curl, base64, nc, netcat, ncat, ssh, socat, wireshark, rawshark, rdesktop, nmap. These commands match a few techniques from the tactics "Command and Control", including not exhaustively the following; Application Layer Protocol (T1071), Non-Application Layer Protocol (T1095), Data Encoding (T1132)

Linuxauditd
TA0011 · Command and Control
Marie EulerMon May 18linux
Detectionmediumexperimental

Potential Abuse of Linux Magic System Request Key

Detects the potential abuse of the Linux Magic SysRq (System Request) key by adversaries with root or sufficient privileges to silently manipulate or destabilize a system. By writing to /proc/sysrq-trigger, they can crash the system, kill processes, or disrupt forensic analysis—all while bypassing standard logging. Though intended for recovery and debugging, SysRq can be misused as a stealthy post-exploitation tool. It is controlled via /proc/sys/kernel/sysrq or permanently through /etc/sysctl.conf.

Linuxauditd
TA0002 · ExecutionT1059.004 · Unix ShellTA0040 · ImpactT1529 · System Shutdown/Reboot+2
Milad CheraghiFri May 23linux
Detectionmediumtest

Systemd Service Creation

Detects a creation of systemd services which could be used by adversaries to execute malicious code.

Linuxauditd
TA0004 · Privilege EscalationTA0003 · PersistenceT1543.002 · Systemd Service
Pawel MazurThu Feb 03linux
Detectionmediumtest

Unix Shell Configuration Modification

Detect unix shell configuration modification. Adversaries may establish persistence through executing malicious commands triggered when a new shell is opened.

Linuxauditd
TA0004 · Privilege EscalationTA0003 · PersistenceT1546.004 · .bash_profile and .bashrc
Peter Matkovski+1Mon Mar 06linux
Detectionmediumexperimental

Clear or Disable Kernel Ring Buffer Logs via Syslog Syscall

Detects the use of the `syslog` syscall with action code 5 (SYSLOG_ACTION_CLEAR), (4 is SYSLOG_ACTION_READ_CLEAR and 6 is SYSLOG_ACTION_CONSOLE_OFF) which clears the kernel ring buffer (dmesg logs). This can be used by attackers to hide traces after exploitation or privilege escalation. A common technique is running `dmesg -c`, which triggers this syscall internally.

Linuxauditd
TA0005 · Defense EvasionT1070.002 · Clear Linux or Mac System Logs
Milad CheraghiTue May 27linux
Detectionmediumtest

Creation Of An User Account

Detects the creation of a new user account. Such accounts may be used for persistence that do not require persistent remote access tools to be deployed on the system.

Linuxauditd
T1136.001 · Local AccountTA0003 · Persistence
Marie Euler+1Mon May 18linux
Detectionmediumtest

Program Executions in Suspicious Folders

Detects program executions in suspicious non-program folders related to malware or hacking activity

Linuxauditd
T1587 · Develop CapabilitiesT1584 · Compromise InfrastructureTA0042 · Resource Development
Florian Roth (Nextron Systems)Tue Jan 23linux
Detectionmediumtest

Modifying Crontab

Detects suspicious modification of crontab file.

Linuxcron
TA0004 · Privilege EscalationTA0002 · ExecutionTA0003 · PersistenceT1053.003 · Cron
Pawel MazurSat Apr 16linux