Computer Blocking CORS OPTIONS Request

Question

This is driving me crazy! I'm trying to work with Amazon S3 CORS requests and they are not working on my computer. It seems that my computer is blocking or ignoring the OPTIONS request. If I run a CURL command from my terminal:

curl -i -X OPTIONS http://testing.bennadel.com.s3.amazonaws.com

... I get:

curl: (52) Empty reply from server

However, if I run the same request on a different computer (AirBook) on the same router, I get the expected response (in XML format):

Insufficient information. Origin request header needed.

I've tried flushing my dsn cache (via dscacheutil). I've tried changing my DNS to use Google's public DNS. I've tried restarting my computer. No luck! This computer keeps blocking the OPTIONS request and every other computer that I try allows it.

Suggestions? This computer (iMac) is connecting to my router over WiFi; but, so does the AirBook, which makes successful OPTIONS requests.

Also note, non-OPTIONS requests to the same URL work fine (ie, GET).

Answer 1

More specifically, the problem seems to be in the Web Security module of AnyConnect. I was able to fix the problem by uninstalling and reinstalling AnyConnect with the Web Security option unchecked; or, just by running the websecurity_uninstall.sh script. (This was with AnyConnect 3.1.04074.)

Thanks to the @user3021922 and others for identifying the issue - this was driving me crazy too.