Identifying Secure Mobile Grid Use Cases - Cloud, Grid and High Performance Computing: Emerging Applications - page 201

Table 4. continued

Mis use Case Alteration of information (MC1)

Postconditions
1) The Grid system must not allow the access to unauthorized users
Misuse Case

Masquerade (MC4)

Atta ck Attack on authorized user

The external attacker type pretends to be an authorized user of a system in order to gain access to it or to gain
greater privileges than those it is authorized for.

Summary

Preconditions
1) The external attacker has physical access to the system and the messages exchanged between the user and the Grid.
Interactions
1 User Interactions The journalist sends a request to the Grid to execute certain task.
2 Misuser Interactions The attacker intercepts the request and obtains privileges information and authorized information of the user
(credentials, roles, rights, etc.)
3 Misuser Interactions The attacker sends requests to the Grid presenting authorized credentials of certain authorized user.
4 System Interactions The Grid system receives these requests of the authorized attacker and executes the harmful actions.

Postconditions
1) The Grid system m ust check the identity of the user who sends requests.
2) The Grid system must check the privileges and certificates presented by the user and the authenticity of the certificates.

Table 5. Security use cases for the case study

Security Use Case Ensure Integrity (SUC1)

Use Case Path System Message Integrity

Security Threat A misuser corrupts a message from the system to a user.

Preconditions
1) The misuser has the means to intercept a message from the system to a user.
2) The misuser has the means to modify an intercepted messag
3) The misuser has the means to forward the modified message to the user.
Interactions

System Interactions The system sends a message to a user.

1

The system ensures that modifications to the message will be obvious
to the user

System Actions

The misuser intercepts and modifies the system's message and for-
wards it to the user.

2 Misuser Interactions

User Interactions The user receives the corrupted message.

3

System Actions The system will recognize that the message was corrupted.

4 System Interactions The system will notify the user that the message was corrupted

Postconditions None

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