The remote host is missing an update to hostapd announced via advisory DSA 2557-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%202557-1

Timo Warns discovered that the internal authentication server of hostapd, a user space IEEE 802.11 AP and IEEE 802.1X/WPA/WPA2/EAP Authenticator, is vulnerable to a buffer overflow when processing fragmented EAP-TLS messages. As a result, an internal overflow checking routine terminates the process. An attacker can abuse this flaw to conduct denial of service attacks via crafted EAP-TLS messages prior to any authentication. For the stable distribution (squeeze), this problem has been fixed in version 0.6.10-2+squeeze1. For the testing (wheezy) and unstable (sid) distributions, this problem will be fixed soon. We recommend that you upgrade your hostapd packages.