CWE-406: Insufficient Control of Network Message Volume (Network Amplification)
Weakness ID: 406
The software does not sufficiently monitor or control transmitted network traffic volume, so that an actor can cause the software to transmit more traffic than should be allowed for that actor.
In the absence of a policy to restrict asymmetric resource consumption, the application or system cannot distinguish between legitimate transmissions and traffic intended to serve as an amplifying attack on target systems. Systems can often be configured to restrict the amount of traffic sent out on behalf of a client, based on the client's origin or access level. This is usually defined in a resource allocation policy. In the absence of a mechanism to keep track of transmissions, the system or application can be easily abused to transmit asymmetrically greater traffic than the request or client should be permitted to.
System resources can be quickly consumed leading to poor application
performance or system crash. This may affect network performance and
could be used to attack other systems and applications relying on
Enabling Factors for Exploitation
If the application uses UDP, then it could potentially be subject to
spoofing attacks that use the inherent weaknesses of UDP to perform traffic
amplification, although this problem can exist in other protocols or
This code listens on a port for DNS requests and sends the result
to the requesting address.
This code sends a DNS record to a requesting IP address. UDP allows
the source IP address to be easily changed ('spoofed'), thus allowing an
attacker to redirect responses to a target, which may be then be
overwhelmed by the network traffic.