Azure Sentinel

@AzureSentinel
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1,223 detections

Finding base64 encoded PE files header seen in the command line parameters.
Tags: #fileLess #powershell.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0036
This query helps reviewing URL click count by ClickAction
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1036
Intent:
- Use MTP capability to look for insider threat potential risk indicators
- Indicators would then serve as the building block for insider threat risk modeling in subsequent tools
Definition of Insider Threat:
"The potential for an individual who has or had authorized access to an organization's assets to use their access, either maliciously or unintentionally, to act in a way that could negatively affect the organization."
This collection of queries describes the different indicators that could be used to model and look for patterns suggesting an increased risk of an individual becoming a potential insider threat.
Note: no single indicator should be used as a lone determinant of insider threat activity, but should be part of an overall program to understand the increased risk to your organization's critical assets. This in turn is used to feed an investigation by a formal insider threat program to look at the context associated with the whole person to understand the implication of a set of indicators.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2036
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 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.
During a typical Ryuk campaign, an operator will use LaZagne, a credential theft tool, to access stored passwords for service accounts. The accounts are then used to jump from desktop clients to servers or domain controllers, allowing for better reconnaissance, faster movement, and a more severe impact on the target.
The following query detects credential theft by LaZagne.
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://github.com/AlessandroZ/LaZagne
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1036
This query helps in reviewing top policies for user overrides (Allow/Block)
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0021
'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
'Detects suspicious user agent strings used by crypto miners in proxy logs.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1036
'Identifies a match for XSS attack in the Application gateway WAF logs. The Threshold value in the query can be changed as per your infrastructure's requirement.
References: https://owasp.org/www-project-top-ten/2017/A7_2017-Cross-Site_Scripting_(XSS)'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2036
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