Detections

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

2,686 detections

Identifies anomalous increases in Exchange mail items accessed operations.
The query leverages KQL built-in anomaly detection algorithms to find large deviations from baseline patterns.
Sudden increases in execution frequency of sensitive actions should be further investigated for malicious activity.
Manually change scorethreshold from 1.5 to 3 or higher to reduce the noise based on outliers flagged from the query criteria.
Read more about MailItemsAccessed- https://docs.microsoft.com/microsoft-365/compliance/advanced-audit?view=o365-worldwide#mailitemsaccessed
Query insprired by Azure Sentinel detection https://github.com/Azure/Azure-Sentinel/blob/master/Detections/OfficeActivity/MailItemsAccessedTimeSeries.yaml
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0038
'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
'IP addresses of broadband links that usually indicates users attempting to access their home network, for example for a remote session to a home computer.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1037
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
Microsoft has observed Bazacall using a renamed version of Rclone for data exfiltration.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1035
'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
As described in previous guidance, Nobelium may re-purpose legitimate existing OAuth Applications in the environment to their own ends. However, malicious activity patterns may be discernable from legitimate ones.
The following query returns OAuth Applications that access mail both directly and via Graph, allowing review of whether such dual access methods follow expected use patterns.
Reference - https://msrc-blog.microsoft.com/2020/12/13/customer-guidance-on-recent-nation-state-cyber-attacks/
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1035
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
0035
'Identifies when multiple (more than one) users mailboxes are configured to forward to the same destination.
This could be an attacker-controlled destination mailbox configured to collect mail from multiple compromised user accounts.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1035
This query helps you review all OAuth applications accessing user mail via Graph. It could return a significant number of results depending on how many applications are deployed in the environment.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0034
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
0034
This detection approach correlates a user accessing an email with image/document attachments and a risky sign-in attempt from non-trusted devices.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0033
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
2033
'This detection will identify network requests in HTTP proxy data that contains Base64 encoded usernames from machines in the DeviceEvents table.
This technique was seen usee by POLONIUM in their RunningRAT tool.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0033
'This hunting query looks for hosts exporting a mailbox from an on-prem Exchange server, followed by
that same host removing the export within a short time window. This pattern has been observed by attackers
when exfiltrating emails from a target environment. A Mailbox export is unlikely to be a common command run so look for
activity from unexpected hosts and accounts.
Reference: https://www.volexity.com/blog/2020/12/14/dark-halo-leverages-solarwinds-compromise-to-breach-organizations/'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1031
This query was originally published in the threat analytics report, "Exchange Server zero-days exploited in the wild".
In early March 2021, Microsoft released patches for four different zero-day vulnerabilities affecting Microsoft Exchange Server. The vulnerabilities were being used in a coordinated attack. For more information on the vulnerabilities, visit the following links:
1. CVE-2021-26855
2. CVE-2021-26857
3. CVE-2021-26858
4. CVE-2021-27065
The following query detects 7-zip activity associated with this threat. 7-ZIP is a legitimate tool used for file archiving; however, unusual 7-ZIP activity combined with other evidence might indicate that an attacker is compressing data for exfiltration.
More queries related to this threat can be found under the See also section of this page.
Reference - https://msrc-blog.microsoft.com/2021/03/02/multiple-security-updates-released-for-exchange-server/
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2030
'This hunting query identifies a fork activity against a repository done by a user who is not the owner of the repo nor a contributes.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
3030
'This hunting query looks for anomalously large LA queries by users.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1030
Snip3 is a family of related remote access trojans. Although the malware in this family contain numerous small variations, they all exhibit similar behaviors and techniques.
The following query looks for network connections using any protocols associated with recent RevengeRAT, AsyncRAT, and other malware campaigns targeting the aviation industry.
This activity is often followed by connections to copy-and-paste sites such as pastebin.com, stikked.ch, academia.edu, and archive.org. Many of these connections will occur on non-standard ports.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0029
'This hunting query looks for new Service Principals running queries that have not previously been seen running queries.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2029
This query can be used to detect instances of a malicious insider creating a file archive and then emailing that archive to an external "competitor" organization.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1028
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