Vulnerability Note VU#893726

Zyxel P660 series modem/router denial of service vulnerability

Original Release date: 01 Apr 2014 | Last revised: 01 Apr 2014

Overview

Zyxel P660 series modem/router contains a denial of service vulnerability when parsing a high volume of SYN packets on the web management interface.

Description

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).

Impact

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.

Solution

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 Updated
ZyXELAffected17 Jun 201331 Jul 2013
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base 7.1 AV:N/AC:M/Au:N/C:N/I:N/A:C
Temporal 5.4 E:U/RL:U/RC:UC
Environmental 4.1 CDP:ND/TD:M/CR:ND/IR:ND/AR:ND

References

Credit

Thanks to Alex French for reporting this vulnerability.

This document was written by Michael Orlando.

Other Information

  • CVE IDs: CVE-2013-3588
  • Date Public: 06 Aug 2013
  • Date First Published: 01 Apr 2014
  • Date Last Updated: 01 Apr 2014
  • Document Revision: 11

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