A digital signature is a mathematical algorithm that validates the authenticity and integrity of a message or document by generating a unique hash of the message or document and encrypting it using the sender's private key1. The primary reason for using a digital signature is to authenticate the sender of a message, as only the sender has access to their private key and can produce a valid signature2. A digital signature also verifies the integrity of the data, as any modification to the message or document will result in a different hash value and invalidate the signature1. However, a digital signature does not provide availability or confidentiality to the transmission, as it does not prevent denial-of-service attacks or encrypt the entire message or document3.
References
1: Understanding Digital Signatures | CISA
2: Signature Verification | CISA
3: SECFND: Digital Signatures from Skillsoft | NICCS

The associated risk of mobile computing that an IS auditor should identify during the planning phase of a data loss prevention (DLP) audit is increased vulnerability due to anytime, anywhere accessibility. Mobile computing refers to the use of portable devices, such as laptops, tablets, smartphones, or wearable devices, that can access data and applications over wireless networks from any location6. Mobile computing enables greater flexibility, productivity, and convenience for users, but also poses significant security challenges for organizations. One of these challenges is increased vulnerability due to anytime, anywhere accessibility. This means that mobile devices are exposed to a higher risk of loss, theft, damage, or unauthorized access than stationary devices7. If mobile devices contain or access sensitive data without proper protection, such as encryption or authentication, they could result in data leakage or breach in case of compromise8. Therefore, an IS auditor should identify this risk as part of a DLP audit. The other options are less relevant or incorrect because:
* A. The use of cloud negatively impacting IT availability is not an associated risk of mobile computing that an IS auditor should identify during the planning phase of a DLP audit, as it is more related to cloud computing than mobile computing. Cloud computing refers to the delivery of computing services, such as data storage or processing, over the Internet from remote servers. Cloud computing may enable or support mobile computing by providing access to data and applications from any device or location, but it does not necessarily imply mobile computing. The use of cloud may negatively impact IT availability if there are disruptions or outages in the cloud service provider's network or infrastructure, but this is not a direct consequence of mobile computing.
* B. Increased need for user awareness training is not an associated risk of mobile computing that an IS auditor should identify during the planning phase of a DLP audit, as it is more of a control or mitigation measure than a risk. User awareness training refers to educating users about security policies, procedures, and best practices for using mobile devices and protecting data. User awareness training may help to reduce the risk of data loss or breach due to mobile computing by increasing user knowledge and responsibility, but it does not eliminate or prevent the risk.
* D. Lack of governance and oversight for IT infrastructure and applications is not an associated risk of mobile computing that an IS auditor should identify during the planning phase of a DLP audit, as it is more of a general or organizational risk than a specific or technical risk. Governance and oversight refer to the establishment and implementation of policies, standards, and procedures for managing IT resources and aligning them with business objectives. Lack of governance and oversight for IT infrastructure and applications may affect the security and performance of mobile devices and data, but it is not a direct or inherent result of mobile computing. References: Mobile Computing - ISACA, Mobile Computing Device Threats, Vulnerabilities and Risk Factors Are Ubiquitous - ISACA, Data Loss Prevention-Next Steps - ISACA, [Cloud Computing - ISACA], [Cloud Computing Risk Assessment - ISACA], [User Awareness Training - ISACA], [Governance and Oversight - ISACA]