论文标题
我们中间的冒名顶替者（b）：对USB通信的分数注射攻击
The Impostor Among US(B): Off-Path Injection Attacks on USB Communications
论文作者
论文摘要
USB是现代计算机系统中最普遍的外围界面，其固有的不安全感使其成为吸引人的攻击向量。 USB的一个众所周知的局限性是流量没有加密。这使得对手能够琐碎地执行中间人的攻击。损害沟通机密性的分数攻击也已被证明是可能的。但是，到目前为止，还没有证明违反USB通信完整性的情况。 在这项工作中，我们表明，即使是针对核对攻击者，也不能保证USB通信的完整性。特别是，我们设计和构建恶意设备，即使将受害者设备和主机之间的路径放在路径外时，也可以将数据注入该路径。使用我们开发的喷油器，我们可以伪造主机计算机系统解释的数据输入的出处。通过代表受信任的受害设备注射，我们可以规避计算机系统针对常见USB攻击的任何基于软件的授权策略防御。我们演示了两次具体攻击。第一个注入击键，允许攻击者执行命令。第二个演示了替换文件包含，包括在USB磁盘中安装过程中。我们测试了对29个USB 2.0和USB 3.x枢纽的攻击，发现其中14个很脆弱。
USB is the most prevalent peripheral interface in modern computer systems and its inherent insecurities make it an appealing attack vector. A well-known limitation of USB is that traffic is not encrypted. This allows on-path adversaries to trivially perform man-in-the-middle attacks. Off-path attacks that compromise the confidentiality of communications have also been shown to be possible. However, so far no off-path attacks that breach USB communications integrity have been demonstrated. In this work we show that the integrity of USB communications is not guaranteed even against off-path attackers.Specifically, we design and build malicious devices that, even when placed outside of the path between a victim device and the host, can inject data to that path. Using our developed injectors we can falsify the provenance of data input as interpreted by a host computer system. By injecting on behalf of trusted victim devices we can circumvent any software-based authorisation policy defences that computer systems employ against common USB attacks. We demonstrate two concrete attacks. The first injects keystrokes allowing an attacker to execute commands. The second demonstrates file-contents replacement including during system install from a USB disk. We test the attacks on 29 USB 2.0 and USB 3.x hubs and find 14 of them to be vulnerable.
