Merge pull request #963 from diskurse/rule-devel

win_webshell_regeorg.yml

rules/web/win_webshell_regeorg.yml

@@ -0,0 +1,37 @@
+title: Webshell ReGeorg Detection Via Web Logs
+id: 2ea44a60-cfda-11ea-87d0-0242ac130003
+status: experimental
+description: Certain strings in the uri_query field when combined with null referer and null user agent can indicate activity associated with the webshell ReGeorg.
+author: Cian Heasley
+reference:
+    - https://community.rsa.com/community/products/netwitness/blog/2019/02/19/web-shells-and-netwitness-part-3
+    - https://github.com/sensepost/reGeorg
+date: 2020/08/04
+tags:
+    - attack.privilege_escalation
+    - attack.persistence
+    - attack.t1100
+    - attack.t1505.003
+logsource:
+    category: webserver
+detection:
+    selection:
+        uri_query|contains:
+            - '*cmd=read*'
+            - '*connect&target*'
+            - '*cmd=connect*'
+            - '*cmd=disconnect*'
+            - '*cmd=forward*'
+    filter:
+        referer: null
+        useragent: null
+        method: POST
+    condition: selection and filter
+fields:
+    - uri_query
+    - referer
+    - method
+    - useragent
+falsepositives:
+    - web applications that use the same URL parameters as ReGeorg
+level: high