There appears to be a whole in the security or something strange is happening with the Knowledge base. Someone appears to be injecting posts into one of the forums that the permissions are set to admin. Here is what they are injecting as a guest. I have deleted the Test Article from the Knowledge base admin area and also in the forums but they keep reappearing. What makes me believe it is an injection is the IP of the poster is not mine.
[KB] Test Article
Article Name: Test Article
Author: Scott
Description: This is a test article for your KB
Category: Test Category 1
Type: Test Type 1
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Have you had any issues on this site regarding this?