Detections

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

837 detections

Author: alex verboon @alexverboon.
Blogpost: https://www.verboon.info/2020/09/hunting-for-local-group-membership-changes.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
7045
'Identifies when a recently created Group was added to a privileged built in domain local group or global group such as the Enterprise Admins, Cert Publishers or DnsAdmins. Be sure to verify this is an expected addition.
References: For AD SID mappings - https://docs.microsoft.com/windows/security/identity-protection/access-control/active-directory-security-groups.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2046
'Identifies accounts that have been added to a PIM managed privileged group'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2045
'Identifies IPs with failed attempts to sign in to one or more disabled accounts signed in successfully to another account.
This analytic will additionally identify the successful signed in accounts as the mapped account entities for investigation.
References: https://docs.microsoft.com/azure/active-directory/reports-monitoring/reference-sign-ins-error-codes
50057 - User account is disabled. The account has been disabled by an administrator.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
9045
'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 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 identity add through exchange PowerShell
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0040
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
'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
'This query detects domain user accounts creation (event ID 4720) where the username ends with $.
Accounts that end with $ are normally domain computer accounts and when they are created the event ID 4741 is generated instead.
Ref: https://blog.menasec.net/2019/02/threat-hunting-6-hiding-in-plain-sights.html'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1038
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
'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
'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
1034
'This query detects an abuse of the DSRM account in order to maintain persistence and access to the organization's Active Directory.
Ref: https://adsecurity.org/?p=1785'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0034
This query lists Active Directory accounts lockout and unlock events
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2033
'Any Alerts that fired related to a given account during the range of +6h and -3d'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0031
One of the indicators of compromise for the Nobelium (formerly Solorigate) campaign was that unexpected service principals have been added to privileged roles. This query looks for service principals that have been added to any role.
See Understanding "Solorigate"'s Identity IOCs - for Identity Vendors and their customers..
Reference - https://techcommunity.microsoft.com/t5/azure-active-directory-identity/understanding-quot-solorigate-quot-s-identity-iocs-for-identity/ba-p/2007610
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0029
'Detects a successful logon by a privileged account from an ASN not logged in from in the last 14 days.
Monitor these logons to ensure they are legitimate and identify if there are any similar sign ins.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0030
Adversaries may manipulate accounts to maintain access to victim systems.
Account manipulation may consist of any action that preserves adversary access to a compromised account, such as modifying credentials or permission groups
Yamato Security Hayabusa@YamatoSecurityHayabusa
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Yamato Security Hayabusa Rules
1 year ago
005
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