I just learned that my load balancer is vulnerable to the POODLE attack due to SSL 3. The recommended solution is to disable SSL 3.

I explained my HAProxy setup in a previous post, and also how I do SSL termination.

The section from my configuration I care about is:

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frontend https-in
        bind *:443 ssl crt /certs/ncona.pem

        acl ncona-web-frontend hdr(host) -i ncona.com www.ncona.com

        use_backend ncona-web if ncona-web-frontend

This mode is called SSL offloading in HAProxy terms. Fixing it is as simple as adding a keyword (no-sslv3):

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        bind *:443 ssl crt /certs/ncona.pem no-sslv3
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