Someone is generating numerous hits to install.php on my server. The actual location of the file, /wp-admin/install.php, has received 11 hits so far this month. But my error logs also show that "/wp-admin/install.php" was appended to many of my archives URLs, giving a series of 404 errors for URLs like this:
/archives/category/catname/wp-admin/install.php
/archives/2005/10/105/wp-admin/install.php
What's going on?