TP-Link TL-WR740N 4 with firmware 3.17.0 Build 140520, 3.16.6 Build 130529, and 3.16.4 Build 130205 allows remote attackers to cause a denial of service (httpd crash) via vectors involving a "new" value in the isNew parameter to PingIframeRpm.htm.
https://exchange.xforce.ibmcloud.com/vulnerabilities/98927
http://www.zeroscience.mk/en/vulnerabilities/ZSL-2014-5210.php
http://www.exploit-db.com/exploits/35345
http://packetstormsecurity.com/files/129227/TP-Link-TL-WR740N-Denial-Of-Service.html