Recently I started seeing lot of activity in my Apache logs. For those that don't know, they are at /private/var/log/httpd (access_log and error_log). The code was:
63.82.46.11 - - [07/Aug/2001:04:06:38 -0700] "GET /default.ida?[Editor's note: Carriage returns inserted, and repetitive "X" characters snipped, to aid readability; this will appear as one line in your log].
XXXXXXXXX...snipped...XXX%u9090%u6858%ucbd3%u7801%u9090%u6858%ucbd3
%u7801%u9090%u6858%ucbd3%u7801%u9090%u9090%u8190%u00c3%u0003
%u8b00%u531b%u53ff%u0078%u0000%u00=a HTTP/1.0" 404 27
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