一句话：指出 Intel SGX enclave 与宿主应用之间的双向接口是主要攻击面，需通过谨慎设计和防御性编程加固。
论文聚焦 Intel SGX 可信执行环境中的 enclave 接口安全。SGX 采用强威胁模型：仅 CPU 可信，内存、固件、系统软件等均不可信。Enclave 通过暴露的、通常双向的接口与宿主应用交互，该接口因而成为主要攻击面；攻击者可以任意顺序和任意输入调用它。作者强调必须通过谨慎的接口设计与防御性编程来保护该接口。标题中的 COIN Attacks 指针对这一接口的攻击类别，但摘要未给出具体攻击构造、实现或评估结果。
Intel SGX is a hardware-based trusted execution environment (TEE), which enables an application to compute on confidential data in a secure enclave. SGX assumes a powerful threat model, in which only the CPU itself is trusted; anything else is untrusted, including the memory, firmware, system software, etc. An enclave interacts with its host application through an exposed, enclave-specific, (usually) bi-directional interface. This interface is the main attack surface of the enclave. The attacker can invoke the interface in any order and inputs. It is thus imperative to secure it through careful design and defensive programming.