EMPhone:通过智能手机上的无声音频播放进行电磁隐蔽通道
Yongjae Kim1, Hyeonjun An2, Dong-Guk Han2
1Department of Information Security, Cryptography and Mathematics, Kookmin University, Seoul 02707, Republic of Korea.
Sensors (Basel, Switzerland)
|September 27, 2025
概括
这项研究揭示了现代智能手机上的新型电磁隐蔽通道,利用音频播放延迟进行隐藏数据传输. 这种实际的安全威胁可以在三星Galaxy设备上以高达0.772 bps的速度进行秘密通信.
科学领域:
- 网络安全 网络安全
- 移动设备安全 移动设备安全
- 信息理论 信息理论
背景情况:
- 智能手机上的秘密通道存在重大安全风险.
- 以前用于电磁 (EM) 隐蔽通道的方法在较新的设备上是无效的.
- 现代智能手机需要新的方法来检测和减轻隐藏通信.
研究的目的:
- 在三星Galaxy S21,S22和S23智能手机上实施和评估一种全新的端到端电磁隐蔽通道.
- 识别和利用新的信号生成方法进行秘密通信.
- 评估开发的EM隐形通道的可靠性,稳定性和数据速率.
主要方法:
- 分析0.1-2.5 MHz范围内的电磁辐射,以识别体积独立的信号.
- 利用静音音频播放后硬件恢复延迟进行信号生成.
- 开发一个隐蔽的Android应用程序,基于时间的调制和专门的调制解调技术.
- 对调制时间,探测距离和消息长度的实验验证.
主要成果:
- 在现代的三星Galaxy智能手机上成功实施和评估了一种新的EM隐蔽通道.
- 通过利用音频播放恢复延迟产生一致的,与音量无关的信号.
- 实现了0.558bps (Galaxy S21) 和0.772bps (Galaxy S22/S23) 的最大无错误位速率.
- 靠近场探测器可实现高达0.5厘米的可靠通信,保持100字节消息的低位错误率.
结论:
- 这项研究确立了现代智能手机上EM隐形通道构成的实际和重大安全威胁.
- 开发的系统证明了使用微妙的电磁辐射进行隐蔽数据传输的可行性.
- 建议采取对策来缓解移动设备中新发现的漏洞.
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