Rule Library

Sigma Rules

1,701 rules found

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

Activity From Anonymous IP Address

Identifies that users were active from an IP address that has been identified as an anonymous proxy IP address.

Azureriskdetection
T1078 · Valid AccountsTA0003 · PersistenceTA0005 · Defense EvasionTA0004 · Privilege Escalation+1
Mark Morowczynski+1Sun Sep 03cloud
Detectionhightest

Anonymous IP Address

Indicates sign-ins from an anonymous IP address, for example, using an anonymous browser or VPN.

Azureriskdetection
T1528 · Steal Application Access TokenTA0006 · Credential Access
Gloria LeeTue Aug 22cloud
Detectionhightest

Atypical Travel

Identifies two sign-ins originating from geographically distant locations, where at least one of the locations may also be atypical for the user, given past behavior.

Azureriskdetection
T1078 · Valid AccountsTA0003 · PersistenceTA0005 · Defense EvasionTA0004 · Privilege Escalation+1
Mark Morowczynski+1Sun Sep 03cloud
Detectionhightest

Impossible Travel

Identifies user activities originating from geographically distant locations within a time period shorter than the time it takes to travel from the first location to the second.

Azureriskdetection
T1078 · Valid AccountsTA0003 · PersistenceTA0005 · Defense EvasionTA0004 · Privilege Escalation+1
Mark Morowczynski+1Sun Sep 03cloud
Detectionhightest

Suspicious Inbox Forwarding Identity Protection

Indicates suspicious rules such as an inbox rule that forwards a copy of all emails to an external address

Azureriskdetection
T1114.003 · Email Forwarding RuleTA0009 · Collection
Mark Morowczynski+1Sun Sep 03cloud
Detectionhightest

Suspicious Inbox Manipulation Rules

Detects suspicious rules that delete or move messages or folders are set on a user's inbox.

Azureriskdetection
T1140 · Deobfuscate/Decode Files or InformationTA0005 · Defense Evasion
Mark Morowczynski+1Sun Sep 03cloud
Detectionhightest

Azure AD Account Credential Leaked

Indicates that the user's valid credentials have been leaked.

Azureriskdetection
T1589 · Gather Victim Identity InformationTA0043 · Reconnaissance
Mark Morowczynski+1Sun Sep 03cloud
Detectionhightest

Malicious IP Address Sign-In Failure Rate

Indicates sign-in from a malicious IP address based on high failure rates.

Azureriskdetection
T1090 · ProxyTA0011 · Command and Control
Mark Morowczynski+1Thu Sep 07cloud
Detectionhightest

Malicious IP Address Sign-In Suspicious

Indicates sign-in from a malicious IP address known to be malicious at time of sign-in.

Azureriskdetection
T1090 · ProxyTA0011 · Command and Control
Mark Morowczynski+1Thu Sep 07cloud
Detectionhightest

Sign-In From Malware Infected IP

Indicates sign-ins from IP addresses infected with malware that is known to actively communicate with a bot server.

Azureriskdetection
T1090 · ProxyTA0011 · Command and Control
Mark Morowczynski+1Sun Sep 03cloud
Detectionhightest

New Country

Detects sign-ins from new countries. The detection considers past activity locations to determine new and infrequent locations.

Azureriskdetection
T1078 · Valid AccountsTA0003 · PersistenceTA0005 · Defense EvasionTA0004 · Privilege Escalation+1
Mark Morowczynski+1Sun Sep 03cloud
Detectionhightest

Password Spray Activity

Indicates that a password spray attack has been successfully performed.

Azureriskdetection
T1110 · Brute ForceTA0006 · Credential Access
Mark Morowczynski+1Sun Sep 03cloud
Detectionhightest

Primary Refresh Token Access Attempt

Indicates access attempt to the PRT resource which can be used to move laterally into an organization or perform credential theft

Azureriskdetection
T1528 · Steal Application Access TokenTA0006 · Credential Access
Mark Morowczynski+1Thu Sep 07cloud
Detectionhightest

Suspicious Browser Activity

Indicates anomalous behavior based on suspicious sign-in activity across multiple tenants from different countries in the same browser

Azureriskdetection
T1078 · Valid AccountsTA0003 · PersistenceTA0005 · Defense EvasionTA0004 · Privilege Escalation+1
Mark Morowczynski+1Sun Sep 03cloud
Detectionhightest

Azure AD Threat Intelligence

Indicates user activity that is unusual for the user or consistent with known attack patterns.

Azureriskdetection
T1078 · Valid AccountsTA0003 · PersistenceTA0005 · Defense EvasionTA0004 · Privilege Escalation+1
Mark Morowczynski+1Thu Sep 07cloud
Detectionhightest

SAML Token Issuer Anomaly

Indicates the SAML token issuer for the associated SAML token is potentially compromised. The claims included in the token are unusual or match known attacker patterns

Azureriskdetection
T1606 · Forge Web CredentialsTA0006 · Credential Access
Mark Morowczynski+1Sun Sep 03cloud
Detectionhightest

Unfamiliar Sign-In Properties

Detects sign-in with properties that are unfamiliar to the user. The detection considers past sign-in history to look for anomalous sign-ins.

Azureriskdetection
T1078 · Valid AccountsTA0003 · PersistenceTA0005 · Defense EvasionTA0004 · Privilege Escalation+1
Mark Morowczynski+1Sun Sep 03cloud
Detectionhightest

Stale Accounts In A Privileged Role

Identifies when an account hasn't signed in during the past n number of days.

Azurepim
TA0001 · Initial AccessTA0005 · Defense EvasionT1078 · Valid AccountsTA0003 · Persistence+1
Mark Morowczynski+1Thu Sep 14cloud
Detectionhightest

Invalid PIM License

Identifies when an organization doesn't have the proper license for PIM and is out of compliance.

Azurepim
TA0001 · Initial AccessTA0005 · Defense EvasionT1078 · Valid AccountsTA0003 · Persistence+1
Mark Morowczynski+1Thu Sep 14cloud
Detectionhightest

Roles Assigned Outside PIM

Identifies when a privilege role assignment has taken place outside of PIM and may indicate an attack.

Azurepim
TA0001 · Initial AccessTA0005 · Defense EvasionT1078 · Valid AccountsTA0003 · Persistence+1
Mark Morowczynski+1Thu Sep 14cloud
Detectionhightest

Roles Activated Too Frequently

Identifies when the same privilege role has multiple activations by the same user.

Azurepim
TA0001 · Initial AccessTA0005 · Defense EvasionT1078 · Valid AccountsTA0003 · Persistence+1
Mark Morowczynski+1Thu Sep 14cloud
Detectionhightest

Roles Are Not Being Used

Identifies when a user has been assigned a privilege role and are not using that role.

Azurepim
TA0001 · Initial AccessTA0005 · Defense EvasionT1078 · Valid AccountsTA0003 · Persistence+1
Mark Morowczynski+1Thu Sep 14cloud
Detectionhightest

Roles Activation Doesn't Require MFA

Identifies when a privilege role can be activated without performing mfa.

Azurepim
TA0001 · Initial AccessTA0005 · Defense EvasionT1078 · Valid AccountsTA0003 · Persistence+1
Mark Morowczynski+1Thu Sep 14cloud
Detectionhightest

Too Many Global Admins

Identifies an event where there are there are too many accounts assigned the Global Administrator role.

Azurepim
TA0001 · Initial AccessTA0005 · Defense EvasionT1078 · Valid AccountsTA0003 · Persistence+1
Mark Morowczynski+1Thu Sep 14cloud
Detectionhightest

Discovery Using AzureHound

Detects AzureHound (A BloodHound data collector for Microsoft Azure) activity via the default User-Agent that is used during its operation after successful authentication.

Azuresigninlogs
TA0007 · DiscoveryT1087.004 · Cloud AccountT1526 · Cloud Service Discovery
Janantha MarasingheSun Nov 27cloud
Detectionhightest

Suspicious SignIns From A Non Registered Device

Detects risky authentication from a non AD registered device without MFA being required.

Azuresigninlogs
TA0004 · Privilege EscalationTA0003 · PersistenceTA0001 · Initial AccessTA0005 · Defense Evasion+1
Harjot SinghTue Jan 10cloud
Detectionhightest

Sign-ins from Non-Compliant Devices

Monitor and alert for sign-ins where the device was non-compliant.

Azuresigninlogs
TA0004 · Privilege EscalationTA0003 · PersistenceTA0001 · Initial AccessTA0005 · Defense Evasion+1
Michael EppingTue Jun 28cloud
Detectionhightest

Potential MFA Bypass Using Legacy Client Authentication

Detects successful authentication from potential clients using legacy authentication via user agent strings. This could be a sign of MFA bypass using a password spray attack.

Azuresigninlogs
TA0004 · Privilege EscalationTA0003 · PersistenceTA0005 · Defense EvasionTA0001 · Initial Access+3
Harjot SinghMon Mar 20cloud
Detectionhightest

Sign-in Failure Due to Conditional Access Requirements Not Met

Define a baseline threshold for failed sign-ins due to Conditional Access failures

Azuresigninlogs
TA0004 · Privilege EscalationTA0003 · PersistenceTA0005 · Defense EvasionTA0001 · Initial Access+3
Yochana HendersonWed Jun 01cloud
Detectionhightest

Use of Legacy Authentication Protocols

Alert on when legacy authentication has been used on an account

Azuresigninlogs
TA0004 · Privilege EscalationTA0003 · PersistenceTA0005 · Defense EvasionTA0001 · Initial Access+3
Yochana HendersonFri Jun 17cloud
Detectionhighexperimental

Azure Login Bypassing Conditional Access Policies

Detects a successful login to the Microsoft Intune Company Portal which could allow bypassing Conditional Access Policies and InTune device trust using a tool like TokenSmith.

Microsoft 365audit
TA0004 · Privilege EscalationTA0003 · PersistenceTA0001 · Initial AccessTA0005 · Defense Evasion+1
Josh Nickels+1Wed Jan 08cloud
Detectionhightest

Disabling Multi Factor Authentication

Detects disabling of Multi Factor Authentication.

Microsoft 365audit
TA0003 · PersistenceTA0005 · Defense EvasionTA0006 · Credential AccessT1556.006 · Multi-Factor Authentication
Splunk Threat Research Team (original rule)+1Mon Sep 18cloud
Detectionhightest

Okta FastPass Phishing Detection

Detects when Okta FastPass prevents a known phishing site.

Oktaokta
TA0001 · Initial AccessT1566 · Phishing
Austin SongerSun May 07identity
Detectionhightest

Okta New Admin Console Behaviours

Detects when Okta identifies new activity in the Admin Console.

Oktaokta
TA0004 · Privilege EscalationTA0003 · PersistenceTA0005 · Defense EvasionTA0001 · Initial Access+1
kelnageThu Sep 07identity
Detectionhightest

Potential Okta Password in AlternateID Field

Detects when a user has potentially entered their password into the username field, which will cause the password to be retained in log files.

Oktaokta
TA0006 · Credential AccessT1552 · Unsecured Credentials
kelnageMon Apr 03identity
Detectionhightest

Okta Suspicious Activity Reported by End-user

Detects when an Okta end-user reports activity by their account as being potentially suspicious.

Oktaokta
TA0042 · Resource DevelopmentT1586.003 · Cloud Accounts
kelnageThu Sep 07identity
Detectionhightest

Okta User Session Start Via An Anonymising Proxy Service

Detects when an Okta user session starts where the user is behind an anonymising proxy service.

Oktaokta
TA0005 · Defense EvasionT1562.006 · Indicator Blocking
kelnageThu Sep 07identity
Detectionhightest

Binary Padding - Linux

Adversaries may use binary padding to add junk data and change the on-disk representation of malware. This rule detect using dd and truncate to add a junk data to file.

Linuxauditd
TA0005 · Defense EvasionT1027.001 · Binary Padding
Igor Fits+1Tue Oct 13linux
Detectionhightest

Credentials In Files - Linux

Detecting attempts to extract passwords with grep

Linuxauditd
TA0006 · Credential AccessT1552.001 · Credentials In Files
Igor Fits+1Thu Oct 15linux
Detectionhighexperimental

ASLR Disabled Via Sysctl or Direct Syscall - Linux

Detects actions that disable Address Space Layout Randomization (ASLR) in Linux, including: - Use of the `personality` syscall with the ADDR_NO_RANDOMIZE flag (0x0040000) - Modification of the /proc/sys/kernel/randomize_va_space file - Execution of the `sysctl` command to set `kernel.randomize_va_space=0` Disabling ASLR is often used by attackers during exploit development or to bypass memory protection mechanisms. A successful use of these methods can reduce the effectiveness of ASLR and make memory corruption attacks more reliable.

Linuxauditd
TA0004 · Privilege EscalationTA0005 · Defense EvasionT1562.001 · Disable or Modify ToolsT1055.009 · Proc Memory
Milad CheraghiMon May 26linux
Detectionhightest

Linux Keylogging with Pam.d

Detect attempt to enable auditing of TTY input

Linuxauditd
TA0009 · CollectionTA0006 · Credential AccessT1003 · OS Credential DumpingT1056.001 · Keylogging
Pawel MazurMon May 24linux
Detectionhightest

Auditing Configuration Changes on Linux Host

Detect changes in auditd configuration files

Linuxauditd
TA0005 · Defense EvasionT1562.006 · Indicator Blocking
Mikhail Larin+1Fri Oct 25linux
Detectionhightest

BPFDoor Abnormal Process ID or Lock File Accessed

detects BPFDoor .lock and .pid files access in temporary file storage facility

Linuxauditd
TA0002 · ExecutionT1106 · Native APIT1059 · Command and Scripting Interpreter
Rafal PiaseckiWed Aug 10linux
Detectionhightest

Modification of ld.so.preload

Identifies modification of ld.so.preload for shared object injection. This technique is used by attackers to load arbitrary code into processes.

Linuxauditd
TA0004 · Privilege EscalationTA0003 · PersistenceTA0005 · Defense EvasionT1574.006 · Dynamic Linker Hijacking
E.M. Anhaus (originally from Atomic Blue Detections+2Thu Oct 24linux
Detectionhightest

Logging Configuration Changes on Linux Host

Detect changes of syslog daemons configuration files

Linuxauditd
TA0005 · Defense EvasionT1562.006 · Indicator Blocking
Mikhail Larin+1Fri Oct 25linux
Detectionhightest

Disable System Firewall

Detects disabling of system firewalls which could be used by adversaries to bypass controls that limit usage of the network.

Linuxauditd
T1562.004 · Disable or Modify System FirewallTA0005 · Defense Evasion
Pawel MazurSat Jan 22linux
Detectionhightest

Loading of Kernel Module via Insmod

Detects loading of kernel modules with insmod command. Loadable Kernel Modules (LKMs) are pieces of code that can be loaded and unloaded into the kernel upon demand. Adversaries may use LKMs to obtain persistence within the system or elevate the privileges.

Linuxauditd
TA0003 · PersistenceTA0004 · Privilege EscalationT1547.006 · Kernel Modules and Extensions
Pawel MazurTue Nov 02linux
Detectionhighstable

Relevant ClamAV Message

Detects relevant ClamAV messages

Linuxclamav
TA0042 · Resource DevelopmentT1588.001 · Malware
Florian Roth (Nextron Systems)Wed Mar 01linux