Detections

Explore public detection logic contributed by the community across SIEM and rule languages.

3,004 detections

This query will find when a new credential is added to an application or service principal.
The Nobelium activity group was able to gain sufficient access to add credentials to existing applications with mail read permissions. They used that access to exfiltrate email.
See Customer Guidance on Recent Nation-State Cyber Attacks for more on the Nobelium campaign (formerly known as Solorigate).
Additional information on OAuth Credential Grants can be found in RFC 6749 Section 4.4 or Microsoft Entra ID audit activity reference.
For further information on AuditLogs please see Microsoft Entra ID audit activity reference.
This query was inspired by an Azure Sentinel detection.
References:
https://msrc-blog.microsoft.com/2020/12/13/customer-guidance-on-recent-nation-state-cyber-attacks/
https://docs.microsoft.com/azure/active-directory/develop/v2-oauth2-client-creds-grant-flow
https://docs.microsoft.com/azure/active-directory/reports-monitoring/reference-audit-activities
https://github.com/Azure/Azure-Sentinel/blob/master/Detections/AuditLogs/NewAppOrServicePrincipalCredential.yaml
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1041
' The query below identifies creation of unusual identity by the Europium actor to mimic Microsoft Exchange Health Manager Service account using Exchange PowerShell commands
Reference: https://www.microsoft.com/security/blog/2022/09/08/microsoft-investigates-iranian-attacks-against-the-albanian-government/'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
3042
This query shows all modifications to highly sensitive active directory groups (also known as Tier 0). An example of these groups include Domain Admins, Schema Admins and Enterprise Admins.
More info can be found here:
https://docs.microsoft.com/security/compass/privileged-access-access-model#evolution-from-the-legacy-ad-tier-model
https://docs.microsoft.com/windows-server/identity/ad-ds/plan/security-best-practices/appendix-c--protected-accounts-and-groups-in-active-directory
This advanced hunting query requires Defender for Identity be deployed due to it's reliance on the IdentityDirectoryEvents table.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
5041
This query looks for Entra ID group adds identified by Microsoft Defender for Cloud Apps. It will require an corresponding app connector in Microsoft Defender for Cloud Apps.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2039
Attackers can use Adfind which is administrative tool to gather information about Domain controllers, ADFS Servers. They may also rename executables with other benign tools on the system.
Below query will look for adfind usage in commandline arguments irrespective of executable name in short span of time. You can limit query this to your DC and ADFS servers.
Below references talk about suspicious use of adfind by adversaries.
- https://thedfirreport.com/2020/05/08/adfind-recon/
- https://www.fireeye.com/blog/threat-research/2020/05/tactics-techniques-procedures-associated-with-maze-ransomware-incidents.html
- https://www.microsoft.com/security/blog/2020/12/18/analyzing-solorigate-the-compromised-dll-file-that-started-a-sophisticated-cyberattack-and-how-microsoft-defender-helps-protect/
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0038
'Compares current day to last 14 days of audits to identify new audit activities. Useful for tracking malicious activity related to user/group additions/removals by specific users.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0039
Detect multiple Active Directory LDAP queries made in bin time
Replace 10 on line 1 with your desired thershold
Replace 1m on line 2 with your desired bin time
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1038
This query will find when federation trust settings are changed for a domain or when the domain is changed from managed to federated authentication. Results will relate to when a new Active Directory Federated Service (ADFS) TrustedRealm object, such as a signing certificate, is added.
Modification to domain federation settings should be rare, so confirm the added or modified target domain/URL is legitimate administrative behavior.
The actor, Nobelium, was observed modifying domain trust settings to subvert existing mechanisms and cause the domain to accept authorization tokens signed with actor-owned certificates. See Customer Guidance on Recent Nation-State Cyber Attacks.
To understand why an authorized user may update settings for a federated domain in Office 365, Azure, or Intune, see Update or repair the settings of a federated domain in Office 365, Azure, or Intune.
For details on security realms that accept security tokens, see the ADFS Proxy Protocol (MS-ADFSPP) specification: 3.2.5.1.2.4 Security Realm Data.
For further information on AuditLogs, please see Microsoft Entra ID audit activity reference.
This query is inspired by an Azure Sentinal detection.
References:
https://msrc-blog.microsoft.com/2020/12/13/customer-guidance-on-recent-nation-state-cyber-attacks/
https://docs.microsoft.com/office365/troubleshoot/active-directory/update-federated-domain-office-365
https://docs.microsoft.com/openspecs/windows_protocols/ms-adfspp/e7b9ea73-1980-4318-96a6-da559486664b
https://docs.microsoft.com/azure/active-directory/reports-monitoring/reference-audit-activities
https://github.com/Azure/Azure-Sentinel/blob/master/Detections/AuditLogs/ADFSDomainTrustMods.yaml
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2038
This query helps in reviewing malicious emails allowed due to admin overrides
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0022
Credentials were added to an application by UserA, after the application was granted admin consent rights by UserB
The Nobelium activity group has been observed adding credentials (x509 keys or password credentials) for one or more legitimate OAuth Applications or Service Principals, usually with existing Mail.Read or Mail.ReadWrite permissions, which grants the ability to read mail content from Exchange Online via Microsoft Graph or Outlook REST. Examples include mail archiving applications.
See Customer Guidance on Recent Nation-State Cyber Attacks for more on the Nobelium campaign (formerly known as Solorigate).
See Grant tenant-wide admin consent to an application for how to add admin consent to an application.
More Nobelium-related queries can be found listed under the See also section of this document.
References:
https://msrc-blog.microsoft.com/2020/12/13/customer-guidance-on-recent-nation-state-cyber-attacks/
https://docs.microsoft.com/azure/active-directory/manage-apps/grant-admin-consent
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
6037
'Identifies when a user account is created and then deleted within 10 minutes. This can be an indication of compromise and an adversary attempting to hide in the noise.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
4037
This will show Active Directory Security Token Service (STS) refresh token modifications by Service Principals and Applications other than DirectorySync. Refresh tokens are used to validate identification and obtain access tokens. This event is most often generated when legitimate administrators troubleshoot frequent Entra ID user sign-ins but may also be generated as a result of malicious token extensions. Confirm that the activity is related to an administrator legitimately modifying STS refresh tokens and check the new token validation time period for high values.
Query insprired by Azure Sentinel detection https://github.com/Azure/Azure-Sentinel/blob/master/Detections/AuditLogs/StsRefreshTokenModification.yaml
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0036
'This hunting query identifies GitHub activites where a repo was changed from private to public that may be a sign of compromise.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1036
'Detects changes to an applications sign out URL.
Look for any modifications to a sign out URL. Blank entries or entries to non-existent locations would stop a user from terminating a session.
Ref: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-applications#logout-url-modified-or-removed'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0036
' This query will detect when an attempt is made to update an existing user and link it to an guest or external identity. These activities are unusual and such linking of external
identities should be investigated. In some cases you may see internal Entra ID sync accounts (Sync_) do this which may be benign'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1036
'Identifies when a user account is enabled and then disabled within 10 minutes. This can be an indication of compromise and an adversary attempting to hide in the noise.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
4036
'This query detects modification in the AdminSDHolder in the Active Directory which could indicate an attempt for persistence.
AdminSDHolder Modification is a persistence technique in which an attacker abuses the SDProp process in Active Directory to establish a persistent backdoor to Active Directory.
This query searches for the event id 5136 where the Object DN is AdminSDHolder.
Ref: https://attack.stealthbits.com/adminsdholder-modification-ad-persistence'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0036
This detection identifies when a new packaged application has been added, updated, or deleted within Microsoft Intune. This functionality, while legitimate for software deployment, can be abused by adversaries to deploy malicious payloads to Intune-managed devices.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0055
This query shows details about all approved Entra ID Governance Access Packages assignments. The results include the time the request was created and approved along with the justification text provided by the requestor and the approver.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0035
'Detects when a guest account in a tenant is converted to a member of the tenant.
Monitoring guest accounts and the access they are provided is important to detect potential account abuse.
Accounts converted to members should be investigated to ensure the activity was legitimate.
Ref: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-user-accounts#monitoring-for-failed-unusual-sign-ins'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1035
'Detects changes to the ownership of an appplicaiton.
Monitor these changes to make sure that they were authorized.
Ref: https://learn.microsoft.com/en-gb/entra/architecture/security-operations-applications#new-owner'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
3034
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