Detections

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

2,686 detections

This query looks for anomalies in mail item access events made by Graph API. It uses standard deviation to determine if the number of events is anomalous. The query returns all clientIDs where the amount of mail sent per day was larger than value given by the formula, 'average + STDThreshold(2.5)*(standard deviation)'.
See The MailItemsAccessed mailbox auditing action.
Reference - https://docs.microsoft.com/microsoft-365/compliance/mailitemsaccessed-forensics-investigations?view=o365-worldwide#the-mailitemsaccessed-mailbox-auditing-action
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0051
'This hunting query will try to identify instances where a file us uploaded to file storage and then deleted
within a given threshold. By default the query will find instances where a file is uploaded and deleted within
5 minutes. This hunting query will help detect automated exfiltration.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2052
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
0049
This query helps hunting for Inbox rule changes which forward-redirect email
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
3048
This query can be used to explore any instances where a terminated individual (i.e. one who has an impending termination date but has not left the company) downloads a large number of files from a non-Domain network address.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1045
Use this query to review OAuth applications whose behaviour has changed as compared to a prior baseline period. The following query returns OAuth Applications accessing user mail via Graph that did not do so in the preceding week.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0045
'CreepyDrive uses OneDrive for command and control, however, it makes regular requests to predicatable paths.
This detecton will alert when over 20 sequences are observed in a single day.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1046
Looks for accounts that uploaded multiple code repositories to external web domain.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1044
'This detection will identify network requests in HTTP proxy data that contains Base64 encoded IP addresses. After identifying candidates the query joins with DeviceNetworkEvents to idnetify any machine within the network using that IP address. Alerts indicate that the IP address of a machine within your network was seen with it's IP address base64 encoded in an outbound web request. This method of egressing the IP was seen used in POLONIUM's RunningRAT tool, however the detection is generic.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1045
'Attacker can exfiltrate data from your GitHub repository by cloning it. This hunting query tracks clone activities for each repository, allowing quick identification of anomalies/excessive clones to investigate repo access & permissions.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1044
'This hunting query will help detect successful sign-ins from devices that are marked non-compliant along with bulk download activity.
Attackers may attempt to get a list of accounts, groups, registration details within an environment which could help in follow-on behavior.
Best practice is to block sign ins from non-complaint devices, however if allowed monitor these events to ensure they do not lead to other risky activity.
Reference: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-devices#non-compliant-device-sign-in'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0044
The following analytic detects the execution of rundll32.exe with command-line arguments loading davclnt.dll and the davsetcookie function to access a remote WebDav instance. It uses data from Endpoint Detection and Response (EDR) agents, correlating process execution and network traffic data. This activity is significant as it may indicate exploitation of CVE-2023-23397, a known vulnerability. If confirmed malicious, this could allow an attacker to establish unauthorized remote connections, potentially leading to data exfiltration or further network compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1051
'This hunting query looks for queries that appear to be looking for secrets or passwords in tables.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2043
This query looks for users accessing multiple other users' mailboxes, or accessing multiple folders in another user's mailbox.
This query is inspired by an Azure Sentinel detection.
Reference - https://github.com/Azure/Azure-Sentinel/blob/master/Hunting%20Queries/OfficeActivity/AnomolousUserAccessingOtherUsersMailbox.yaml
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0042
'This query looks for command lines that contain a public IP address. Attackers may use a hard coded IP for C2 or exfiltration.
This query can be filtered to exclude network prefixes that are known to be legitimate.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2042
Background Intelligent Transfer Service (BITS) is a way to reliably download files from webservers or SMB servers.
This service is commonly used for legitimate purposes, but can also be used as part of a malware downloader.
Additionally, bitsadmin can be used to upload files and therefore can be used for data exfiltration. This
query will identify use of bitsadmin.exe for either purpose and will identify directionality file transfer
directionality.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1041
"This query searches for any files in Cloud App Events that have trigger a security alert."
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
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
avatar
AzureSentinel
1 year ago
1040
This query was originally published in the threat analytics report, MailSniper Exchange attack tool.
MailSniper is a tool that targets Microsoft Exchange Server. The core function is to connect to Exchange Server and search through emails. In support of this, it can perform reconnaissance, collection, exfiltration, and credential theft. MailSniper is used both by red teams running penetration tests, and by malicious actors.
Microsoft Defender Security Center may record the following alerts during and after an attack:
1. Global mail search on Exchange using MailSniper
2. Exchange mailbox or mail folder search using MailSniper
3. Enumeration of Active Directory usernames using MailSniper
4. Enumeration of the Exchange GAL using MailSniper
5. Access to Exchange inboxes using MailSniper
6. Password spraying using MailSniper
7. Enumeration of domains and user accounts using MailSniper
The following query detects activity commonly associated with attacks run with MailSniper.
Reference - https://github.com/dafthack/MailSniper
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0039
'This detection will alert when RunningRAT URI parameters or paths are detect in an HTTP request.
Id the device blocked this communication presence of this alert means the RunningRAT implant is likely still executing on the source host.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0140
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