Detections

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

7 detections

This rule detects HTTP requests to the '.well-known/' directory that include common webshell file extensions (php, cfm, cgi, asp, aspx, jsp, rb, sh, py, pl). This activity is suspicious as the '.well-known/' directory is typically used for standardized metadata files (e.g., for ACME challenges, security.txt) and not for executable scripts. The rule specifically excludes requests from 'Let's Encrypt validation server' to reduce false positives.
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Tim Peck@timpeck
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Proofpoint Emerging Threats Rules
1 year ago
0036
Detects suspicious child processes spawned by SAP NetWeaver on Linux systems that could indicate potential exploitation of a vulnerability that allows arbitrary execution via webshells, such as CVE-2025-31324. The rule looks for common shell interpreters, scripting languages, and network utilities being executed from specific SAP NetWeaver directories.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0034
Detects the creation of suspicious files (jsp, java, class) in specific SAP NetWeaver directories. This activity may indicate an attempt to establish a webshell or exploit vulnerabilities, such as CVE-2025-31324, to gain persistent access or execute arbitrary code within the SAP environment.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0026
'This query looks for messages related to file downloads of suspicious file types on an Exchange Server. This could indicate attempted deployment of webshells.
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.
This log is commonly found at C:\Program Files\Microsoft\Exchange Server\V15\Logging\OABGeneratorLog on the Exchange server. Details on collecting custom logs into Sentinel
can be found here: https://learn.microsoft.com/azure/sentinel/connect-custom-logs
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2030
'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 rule detects relevant ClamAV messages indicating the presence of various types of malware. It specifically looks for keywords like 'Trojan*FOUND', 'VirTool*FOUND', 'Webshell*FOUND', 'Rootkit*FOUND', and 'Htran*FOUND' in ClamAV logs. These keywords suggest that ClamAV has identified and reported a malicious file or component.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
0036
Detects the use of the "appcmd.exe" utility to create or modify global URL rewrite rules within Internet Information Services (IIS). This activity is suspicious because threat actors have been observed leveraging this method to establish persistence or facilitate access to webshells by redirecting traffic or enabling specific paths.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
0014