Detections

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

3,864 detections

'Identifies sign-in anomalies from an IP in the last hour, targeting multiple users where the password is correct after multiple attempts'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1043
This query will find applications that have been granted Mail.Read or Mail.ReadWrite permissions in which the corresponding user recently consented to. It can help identify applications that have been abused to gain access to user email.
The actor, Nobelium, was observed modifying existing tenant application permissions to allow them to read user email through the Microsoft Graph API. See Customer Guidance on Recent Nation-State Cyber Attacks.
This query is insprired by an Azure Sentinel detection.
References:
https://msrc-blog.microsoft.com/2020/12/13/customer-guidance-on-recent-nation-state-cyber-attacks/
https://github.com/Azure/Azure-Sentinel/blob/master/Detections/AuditLogs/MailPermissionsAddedToApplication.yaml
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2042
'Compares the 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 Azure Apps and automated approvals.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2042
'This query look for accounts that have not been successfully logged into recently who then add or update an MFA method before logging in.
Threat actors may look to re-activate dormant accounts and use them for access by adding MFA methods in the hope that changes to such dormant accounts may go un-noticed. This query uses the Microsoft Sentinel UEBA features.
Ref: [LINK TO BLOG]'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0042
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
'This hunting query looks for users who have multiple failed queries in a short space of time.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1041
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
'Identifies modifications to user's MFA settings. An attacker could use access to modify MFA settings to bypass MFA requirements or maintain persistence.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1039
'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
'Identifies a match across various data feeds for domains related to an actor tracked by Microsoft as Star Blizzard.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1039
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
'Looks for users retrieving BitLocker keys. Enriches these logs with a summary of alerts associated with the user accessing the keys.
Use this query to start looking for anomalous patterns of key retrieval.
Ref: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-devices#bitlocker-key-retrieval'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2038
'This hunting query will identify where a file is uploaded to Azure File or Blob storage
and is then accessed once before being deleted. This activity may be indicative of
exfiltration activity.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2038
'This query over Microsoft Entra ID sign-in activity highlights Microsoft Entra ID apps with
an unusually high ratio of distinct geolocations versus total number of authentications'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2038
'Identifies a list of IP addresses with a minimum number (default of 5) of failed logon attempts to AWS Console.
Uses that list to identify any successful Microsoft Entra ID logons from these IPs within the same timeframe.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
3038
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
'Azure AD Connect (AAD Connect) is a critical service that handles connections between on-premise Active Directory and Azure AD.
Due to the critical nature of AAD Connect threat actors may attempt to compromise the service in order to access credentials.
This query looks for SSH connections to host that appear to run AAD Connect. The results should be reviewed to determine if the
SSH connection is legitimate.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0037
Detects when there is a login attempt from a country that has not seen a successful login in the previous 14 days.
Threat actors may attempt to authenticate with credentials from compromised accounts - monitoring attempts from anomalous locations may help identify these attempts.
Authentication attempts should be investigated to ensure the activity was legitimate and if there is other similar activity.
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
2037
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
'Detects when a user has successfully authenticated to another Microsoft Entra ID tenant with an identity in your organization's tenant.
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
0036
'Identifies accounts that have been locked out by smart lockout policies. Review this results for patterns that might suggest that a password spray is triggering these smart lockout events.
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
1036
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