In the cloud-based vehicular ad-hoc network (VANET), massive vehicle information is stored on the cloud, and a large amount of data query, calculation, monitoring, and management are carried out at all times. The secure spatial query methods in VANET allow authorized users to convert the original spatial query to encrypted spatial query, which is called query token and will be processed in ciphertext mode by the service provider. Thus, the service provider learns which encrypted records are returned as the result of a query, which is defined as the access pattern. Since only the correct query results that match the query tokens are returned, the service provider can observe which encrypted data are accessed and returned to the client when a query is launched clearly, and it leads to the leakage of data access pattern. In this paper, a reconstruction attack scheme is proposed, which utilizes the access patterns in the secure query processes, and then it reconstructs the index of outsourced spatial data that are collected from the vehicles. The proposed scheme proves the security threats in the VANET. Extensive experiments on real-world datasets demonstrate that our attack scheme can achieve quite a high reconstruction rate.

中文翻译：

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车载自组织网络中安全外包空间数据集的重构攻击方案

在基于云的车载自组网（VANET）中，海量的车辆信息存储在云端，并时刻进行着大量的数据查询、计算、监控和管理。VANET 中的安全空间查询方法允许授权用户将原始空间查询转换为加密的空间查询，称为查询令牌，将由服务提供者以密文方式处理。因此，服务提供者了解作为查询结果返回哪些加密记录，这被定义为访问模式。由于只返回与查询令牌匹配的正确查询结果，服务提供者在发起查询时可以清楚地观察到哪些加密数据被访问并返回给客户端，从而导致数据访问模式的泄漏。在本文中，提出了一种重构攻击方案，它利用安全查询过程中的访问模式，然后重构从车辆收集的外包空间数据的索引。所提出的方案证明了VANET中的安全威胁。对真实世界数据集的大量实验表明，我们的攻击方案可以实现相当高的重建率。