strange website error

[wanren]

The below is from my apache error log:
[error] [client 114.245.xx.xx] request failed: error reading the headers, referer: http://www.mydomain.com/item.php?act=member&ac=subject_add&pid=16

[error] [client 114.245.xx.xx] Invalid URI in request m.php?act=member&ac=subject_add&rand=R3Z3G HTTP/1.1

website got 404 not found error, anyone has clue?

 

[LawsHosting]

Any of those php files exist? If not, it could be a random scan of a vulnerable script.

 

[wanren]

Any of those php files exist? If not, it could be a random scan of a vulnerable script.

It's just a CMS application, and after refresh the page, it will work...

 

[daveyw]

Do you have mod_security active on your server?

 

[wanren]

Do you have mod_security active on your server?

No, I never install it... the issue is strange, isn't it?