Published:2011/04/11  Last Updated:2011/05/23

Multiple Yamaha routers vulnerable to denial-of-service (DoS)


Multiple routers provided by Yamaha contain a denial-of-service vulnerability.

Products Affected

A wide range of products are affected. For more information, refer to the developer's website.


Multiple routers provided by Yamaha contain a denial-of-service (DoS) vulnerability due to an issue in processing IP packets.


A remote attacker may cause a denial-of-service (DoS).


Update the firmware
Update to the latest version of firmware according to the information provided by the developer.
According to the developer, firmware addressing this vulnerability will be released successively.

Apply a workaround
If updated firmware cannot be obtained, the following workaround may mitigate the affects of this vulnerability.

  • Utilize packet filtering to prevent accepting malicious IP packets

According to the developer, firmware updates for certain models will not be released.

Vendor Status

Vendor Status Last Update Vendor Notes
NEC Corporation vulnerable 2011/04/20
Yamaha Corporation vulnerable 2011/04/11


JPCERT/CC Addendum

Vulnerability Analysis by JPCERT/CC

Analyzed on 2011.04.11

Measures Conditions Severity
Access Required can be attacked over the Internet using packets
  • High
Authentication anonymous or no authentication (IP addresses do not count)
  • High
User Interaction Required the vulnerability can be exploited without an honest user taking any action
  • High
Exploit Complexity some expertise and/or luck required (most buffer overflows, guessing correctly in small space, expertise in Windows function calls)
  • Mid-High

Description of each analysis measures


IP packets that contain invalid values in the IP option header are mostly discarded by the router, therefore an attack through the internet being successful is highly unlikely.


Yuji Ukai of Fourteenforty Research Institute, Inc. reported this vulnerability to IPA.
JPCERT/CC coordinated with the developer under Information Security Early Warning Partnership.

Other Information

JPCERT Reports
CERT Advisory
CPNI Advisory
CVE CVE-2011-1323
JVN iPedia JVNDB-2011-000024

Update History

NEC Corporation update status
JVN iPedia link was added under Other Information
Vulnerability Analysis by JPCERT/CC section updated