Detections

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

4,230 detections

'Identifies connection attempts (success or fail) from clients with very short or very long User Agent strings and with less than 100 connection attempts.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1023
'Rule helps to detect Powershell user-agent activity by an unusual process other than a web browser.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
4021
'This query looks for suspicious request patterns to Exchange servers that fit patterns recently blogged about by PeterJson. This exploitation chain utilises an SSRF vulnerability in Exchange which eventually allows the attacker to execute arbitrary Powershell on the server.
In the example powershell can be used to write an email to disk with an encoded attachment containing a shell.
Reference: https://peterjson.medium.com/reproducing-the-proxyshell-pwn2own-exploit-49743a4ea9a1'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2021
'This will check for Rare User Agent strings over the last 3 days. This can indicate potential probing of your IIS servers.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1020
'Malware can use IP address to communicate with C2.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
9018
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
1017
'The hunting query looks for suspicious files accessed on a IIS server that might indicate exfiltration hosting. This technique has been observed when exporting mailbox files from OWA servers.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0017
'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
'This finds connections to server files requested by only one client. Effective when actor uses static operational IP addresses. Threshold can be modified. Larger execution window increases reliability of results.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0016
'Rule helps to detect empty and unusual user agent indicating web browsing activity by an unusual process other than a web browser.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1016
'This query looks for messages related to file downloads of suspicious file types. This query uses the Exchange HttpProxy AOBGeneratorLog, you will need to onboard this log as a custom log under the table http_proxy_oab_CL before using this query.
Reference: https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1015
'This query will detect paths suspicious associated with ProxyLogon exploitation'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1014
'This query will detect paths suspicious associated with ProxyLogon exploitation, it will then calculate the percentage of suspicious URIs
the user had visited in relation to the total number of URIs the user has visited. This query will assist in the detection of automated
ProxyLogon exploitation.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1013
'Looks for activity that might indicate exploitation of the ProxyToken vulnerability - CVE-2021-33766
Ref: https://www.zerodayinitiative.com/blog/2021/8/30/proxytoken-an-authentication-bypass-in-microsoft-exchange-server'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1013
'This alerts when a client IP connects with 1-15 different useragents in less than 1 hour. Limited to 50 or less connections to avoid high traffic. May indicate malicious activity as a probing method.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0013
Detects a specific user agent string and host ('api.dropbox.com') associated with an APT40 Dropbox tool, indicating potential data exfiltration or command and control activity via Dropbox.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0054
Detects HTTP requests containing the URI pattern '/asp.asp?ui=' which is known to be used by the Chafer malware for command and control communication to receive data from its C2 server.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0029
Detects potential Java webshell uploads to an SAP NetViewer server via HTTP POST requests with a 'Content-Type' of 'application/octet-stream' and URI stems containing '/irj/' and ending with '.jsp', '.class', or '.java'. This behavior might indicate exploitation of vulnerabilities like CVE-2025-31324, which allows remote code execution through webshells.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
1034
Detects the download of Ursnif malware based on specific URL patterns and a successful HTTP status code. The rule looks for URIs containing a forward slash, '.php?l=', and ending with '.cab', combined with an HTTP status code of 200, indicating a successful download.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0025
Detects potential command execution via webshell in SAP NetViewer through JSP files with 'cmd' or similar parameters. This rule is designed to identify exploitation of vulnerabilities like CVE-2025-31324, which allows remote code execution via a webshell by looking for specific URI patterns and query parameters indicative of command execution attempts, including common Linux commands and base64 encoded commands.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0029
URLs clicked in Email
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0015
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