Description
One of the IP Softphone ports is vulnerable to a Denial of Service (DoS) attack when sent a large amount of data.
Recommendations
Avaya has acknowledged the issue and is working on correcting it. More details could be found in Avaya Security Advisory ASA-2008-363 at http://support.avaya.com/elmodocs2/security/ASA-2008-363.htm . In the short term it is recommended that a VoIP aware IPS product, such as VoIPguard, with signatures to detect attempts to exploit this issue, be implemented to prevent it from being exploited. Implementing best practices can limit the exposure of this issue. Implementing stronger authentication can assist in reducing the number of attackers in a position to exploit the issue, though requires additional system management effort. Avaya customers with a valid support agreement may wish to speak with their support contact in order to obtain further vendor details.