Azure Sentinel

@AzureSentinel
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1,223 detections

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
'This query will identify the Microsoft Defender Antivirus Security Intelligence version, Security Intelligence up to date value, Engine version, Engine up to date value, Product version (aka Platform version),Product (aka Platform) up to date value, Security Intelligence publish/build timestamp, Security intel refresh timestamp and provide a list of devices with these details.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
4037
'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 was originally published in the threat analytics report, Ryuk ransomware. There is also a related blog.
Ryuk is human-operated ransomware. Much like DoppelPaymer ransomware, Ryuk is spread manually, often on networks that are already infected with Trickbot.
Ryuk operators use PsExec to manually spread the ransomware to other devices.
The following query detects remote file creation events that might indicate an active attack.
The See also section below lists links to other queries associated with Ryuk ransomware.
References:
https://www.microsoft.com/security/blog/2020/03/05/human-operated-ransomware-attacks-a-preventable-disaster/
https://www.microsoft.com/wdsi/threats/malware-encyclopedia-description?Name=Ransom:Win32/Ryuk&threatId=-2147232689
https://www.microsoft.com/security/blog/2020/03/05/human-operated-ransomware-attacks-a-preventable-disaster/
https://docs.microsoft.com/sysinternals/downloads/psexec
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
0037
Pivot from downloads detected by Windows Defender Antivirus to other files downloaded from the same sites.
To learn more about the download URL info that is available and see other sample queries,.
Check out this blog post: https://techcommunity.microsoft.com/t5/Threat-Intelligence/Hunting-tip-of-the-month-Browser-downloads/td-p/220454.
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
0037
'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
avatar
AzureSentinel
1 year ago
2038
'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
avatar
AzureSentinel
1 year ago
1038
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