Detections

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

782 detections

'This identifies failed logon attempts using permutations based on known first and last names within 10m time windows. Iteration through separators or order changes in the logon name may indicate potential Brute Force logon attempts.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0026
'An account could be blocked/locked out due to multiple reasons. This hunting query summarize blocked/lockout accounts and checks if most recent signin events for them is after last blocked accounts
Ref: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-user-accounts#monitoring-for-successful-unusual-sign-ins'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1026
'Identifies a list of IP addresses with a minimum number(default of 5) of failed logon attempts to remote hosts.
Uses that list to identify any successful logons to Microsoft Entra ID from these IPs within the same timeframe.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1026
'Detects when a privileged user account successfully authenticates from a location, device or ASN that another admin has not logged in from in the last 7 days.
Privileged accounts are a key target for threat actors, monitoring for logins from these accounts that deviate from normal activity can help identify compromised accounts.
Authentication attempts should be investigated to ensure the activity was legitimate and if there is other similar activity.
Ref: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-user-accounts#monitoring-for-successful-unusual-sign-ins'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1026
Looks for users who had a risky sign in (based on Entra ID Identity Protection risk score) and then performed and ElevateAccess action. ElevateAccess operations can be used by Global Admins to obtain permissions over Azure resources.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0025
'Identifies instances where Wazuh logged over 400 '403' Web Errors from one IP Address. To onboard Wazuh data into Sentinel please view: https://github.com/wazuh/wazuh-documentation/blob/master/source/azure/monitoring%20activity.rst'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0025
'Detects a user's consent to an OAuth application being blocked due to it being too risky.
These events should be investigated to understand why the user attempted to consent to the applicaiton and what other applicaitons they may have consented to.
Ref: https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-applications#end-user-stopped-due-to-risk-based-consent'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0025
// Detect Active Directory service accounts that are not active because their last logon was more than 14 days ago
// Replace XXX on line 4 with the naming convention start of your Active Directory service accounts
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
3024
'Query over SigninLogs summarizes login attempts per hour on weekdays. Kusto anomaly detection finds login spikes. Calculates percentage change between anomalous period and average logins. Determines success and failure rate for logins for 1 hour period.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1024
'This identifies when a user account successfully logs onto a given App and within 1 minute fails to logon to a different App.
This may indicate a malicious attempt at accessing disallowed Apps for discovery or potential lateral movement'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0024
'Query identifies users denied registration for multiple webinars or recordings but successfully registered for at least one event. Threshold variable adjusts number of events user needs to be rejected from.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0023
'This query detects authentication attempt from a fake computer account(username ends with $).
Computer accounts are normally not authenticating via interactive logon or remote desktop neither they are unlocking the systems.
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
0122
'Identifies when 20 or more failed attempts from a given client IP in 1 minute occur on the IIS server.
This could be indicative of an attempted brute force. This could also simply indicate a misconfigured service or device.
Recommendations: Validate that these are expected connections from the given Client IP. If the client IP is not recognized, potentially block these connections at the edge device.
If these are expected connections, verify the credentials are properly configured on the system, service, application or device that is associated with the client IP.
References:
IIS status code mapping: https://support.microsoft.com/help/943891/the-http-status-code-in-iis-7-0-iis-7-5-and-iis-8-0
Win32 Status code mapping: https://msdn.microsoft.com/library/cc231199.aspx'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2020
'Identifies IPs with failed attempts to sign in to one or more disabled accounts signed in successfully to another account.
To use this analytics rule, make sure you have deployed the [ASIM normalization parsers](https://aka.ms/ASimAuthentication)'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0019
'User account failed to logon in current period. Excludes Windows Sign in attempts and limits to only more than 10 failed logons or 3 different IPs used. Results may indicate a potential malicious use of an account that is rarely used.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1018
'Identifies when 100 or more failed attempts by a given user in 10 minutes occur on the IIS Server.
This could be indicative of attempted brute force based on known account information.
This could also simply indicate a misconfigured service or device.
References:
IIS status code mapping - https://support.microsoft.com/help/943891/the-http-status-code-in-iis-7-0-iis-7-5-and-iis-8-0
Win32 Status code mapping - https://msdn.microsoft.com/library/cc231199.aspx'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0017
'Identifies when failed logon attempts are 20 or higher during a 10 minute period (2 failed logons per minute minimum) from valid account.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0016
This query helps reviewing authentication failure count by authentication type. Update the authentication type below as DMARC, DKIM, SPM, CompAuth
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0013
Sample query to detect If there are more then 3 failed logon authentications on high value assets.
Update DeviceName to reflect your high value assets.
For questions @MiladMSFT on Twitter or milad.aslaner@microsoft.com.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1010
Query #1: Look for public IP addresses that failed to logon to a computer multiple times, using multiple accounts, and eventually succeeded.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
109
Looks for a new device registration in Entra ID preceded by medium or high-risk sign-in session for the same user within maximum 6h timeframe.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
7057
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