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2.6.3

Infrastructure-as-a-Service (IaaS) Security Issues

We know that IaaS offers a different set of resources, such as servers, storage media,

networks, and other computing structures, in the form of virtual machines accessed

by the Internet, and these devices operate, control, and manage resources [29]. IaaS

enables cloud users to better control security compared to other models, as there is

no security vulnerability in the virtual machine screen [27], with the need to take

into account some threats such as: Registering a client in the cloud as root and

obtaining his permission to access more virtual devices and this what makes user

data threatened (impersonation), also the problem of multiple burden work as a result

of sharing work on the same virtual servers so that the workload must be isolated

which is very important so that the resources are divided among all the workloads in

the data centers, using VMM (Virtual Machine Manager or Hypervisor) is a low-level

program that controls and monitors its virtual machines, which is like any traditional

program that faces security flaws but reduces threats because it facilitates the process

of finding and fixing errors. Virtual Machine Image (VMI) are created by either the

provider or the customer and is also vulnerable to malware. Another threat associated

with Virtual Machine images is that VMIs may store customer or previous owner

information, and this is what is feared to be used by another user, so VMIs must be

deleted well by CSP before using it from another client, virtual networks or VLANs

must also be isolated to get away from the unauthorized flow of data through them,

one attack is the other is when one of the hackers runs its own malicious service

instance or virtual machine instance, and, thus, the opponent is tricked into using

the instance as Valid. Also, VM repetition is one of the reasons that lead to data

leakage so the user must pause the devices during replication to ensure that the

data are integrated [30], the ability of VM devices to move between different data

centers according to the CSP request is one of the important characteristics of it (its

displacement for load balancing [30]), but this makes its security at risk, for both

VM escape and VM hopping significant risks to security and data confidentiality as

well, there are some concerns regarding service availability or failure of a VM using

another alternative instance [27], as a result of DoS attacks On servers.

Therefore, you should always pay attention to the safety of virtual machines

and the life cycle of VMs as well as VMIs, yet the primary controller remains the

Cloud Service Provider. Table 2 gives us the outline of cloud service delivery models

according to security issues.

2.7

Cloud Storage

It is considered a sophisticated model capable of converting storage and computing

capabilities into the hands of external service providers (CSP), but as a result of

the loss of direct control of data, users are reluctant to use cloud services, as data

security and privacy is one of the most important challenges that concern users, for

example in 2013 the Washington Post announced that The US National Security