Strange entry in logs

[diggle]

Spotted this in logs.
Anyone any ideas what it is?
I did not write it as a tracking device.
Thank you for any help.

Jim D

"GET /?source=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

[jdMorgan]

It's a security exploit, trying to overrun your server's input buffer.

Your server should return an error code of 400-Bad Request. If not, get the latest patches installed.

Jim