Cloud Malware Injection Attack. A first considerable
attack attempt aims at injecting a malicious
service implementation or virtual machine into the
Cloud system. Such kind of Cloud malware could
serve any particular purpose the adversary is interested
in, ranging from eavesdropping via subtle data modi-
fications to full functionality changes or blockings.
This attack requires the adversary to create its own
malicious service implementation module (SaaS or
PaaS) or virtual machine instance (IaaS), and add it
to the Cloud system. Then, the adversary has to trick
the Cloud system so that it treats the new service
implementation instance as one of the valid instances
for the particular service attacked by the adversary. If
this succeeds, the Cloud system automatically redirects
valid user requests to the malicious service implementation,
and the adversary’s code is executed.
A promising countermeasure approach to this threat
consists in the Cloud system performing a service instance
integrity check prior to using a service instance
for incoming requests. This can e.g. be done by storing
a hash value on the original service instance’s image
file and comparing this value with the hash values of all
new service instance images. Thus, an attacker would
be required to trick that hash value comparison in order
to inject his malicious instances into the Cloud system.