ieee80211_output.c in MadWifi before 0.9.3 sends unencrypted packets before WPA authentication succeeds, which allows remote attackers to obtain sensitive information (related to network structure), and possibly cause a denial of service (disrupted authentication) and conduct spoofing attacks.
https://exchange.xforce.ibmcloud.com/vulnerabilities/33514
http://www.vupen.com/english/advisories/2007/1187
http://www.ubuntu.com/usn/usn-479-1
http://www.securityfocus.com/bid/23434
http://www.securityfocus.com/archive/1/466689/30/6900/threaded
http://www.novell.com/linux/security/advisories/2007_14_sr.html
http://www.mandriva.com/security/advisories?name=MDKSA-2007:082
http://security.gentoo.org/glsa/glsa-200704-15.xml
http://secunia.com/advisories/26083
http://secunia.com/advisories/25861
http://secunia.com/advisories/24931
http://secunia.com/advisories/24841
http://secunia.com/advisories/24670