Vulnerability Note VU#893726
Zyxel P660 series modem/router denial of service vulnerability
Original Release date: 01 Apr 2014 | Last revised: 01 Apr 2014
Zyxel P660 series modem/router contains a denial of service vulnerability when parsing a high volume of SYN packets on the web management interface.
It has been reported that Zyxel P660 series modem/router (and possibly other models which share the same core firmware) fail to parse a high volume of SYN packets on the web management interface correctly causing the device to reboot. By default, the device runs a web management interface on port tcp/80 which is accessible remotely (LAN and WAN sides).
An unauthenticated attacker can cause the device to reboot and become unavailable by sending a stream of SYN packets to the device’s web management interface.
We are currently unaware of a practical solution to this problem.
Restrict Network Access
As a general good security practice, only allow connections from trusted hosts and networks if possible. Restricting access would prevent an attacker from connecting to the service from a blocked network location.
Vendor Information (Learn More)
VendorStatusDate NotifiedDate UpdatedZyXELAffected17 Jun 201331 Jul 2013If you are a vendor and your product is affected, let
CVSS Metrics (Learn More)
Thanks to Alex French for reporting this vulnerability.
This document was written by Michael Orlando.
06 Aug 2013
Date First Published:
01 Apr 2014
Date Last Updated:
01 Apr 2014
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