[CentOS] decode http hack attempt?

Can anyone de-cypher the second entry for me?

--------------------- httpd Begin ------------------------


 Requests with error response codes
    403 Forbidden
       /: 9 Time(s)
       /?c=4e5e5d7364f443e28fbf0d3ae744a59a: 3 Time(s)

I have found the string via Google but have not located any explanation.

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James B. Byrne                mailto:ByrneJB at Harte-Lyne.ca
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