加密通道是指攻击者使用密码学手段对通信内容进行加密，以保护命令控制（C2）流量免受窃听或分析的网络对抗技术。传统加密通道通常采用固定加密算法与静态密钥，通过与目标系统建立加密会话实现数据隐蔽传输。防御方可通过SSL/TLS解密、流量特征分析、异常协议检测等手段识别潜在恶意加密通信，例如检测不符合协议规范的加密握手过程、识别非常用端口上的加密流量或分析通信模式的时序异常。
当前加密通道匿迹技术的核心演进方向聚焦于加密体系动态化、协议行为拟真化与传输架构去中心化三大维度。动态密钥轮换技术通过密码学参数的持续更新破坏静态特征提取，使得传统基于特征签名的检测方法失效；协议模拟加密隧道在协议栈各层级精确复制合法应用行为，规避深度包检测设备的协议合规性审查；分布式代理链传输则通过多节点加密中继与动态路由机制，将通信特征分散至多个网络空间维度。三类技术的共性在于突破传统加密通道的"端到端"静态模型，构建具备环境自适应能力的弹性加密体系，通过密码学、协议工程与网络拓扑的协同创新，实现加密流量在协议合规性、行为合法性和拓扑隐蔽性层面的全面伪装。
| 效应类型 | 是否存在 |
|---|---|
| 特征伪装 | ✅ |
| 行为透明 | ❌ |
| 数据遮蔽 | ✅ |
| 时空释痕 | ✅ |
攻击者通过协议栈深度模拟技术，使加密通道在协议头结构、握手流程、数据封装等层面与合法加密应用（如HTTPS、SSH）完全一致。部分高级实现还能动态适配目标网络的主流协议类型，使得加密流量在协议解析层面无法与正常业务流量区分，实现通信特征的深度伪装。
采用符合行业标准的强加密算法（如AES-256、ChaCha20）对通信内容进行端到端加密，结合前向安全设计确保历史通信无法被破解。部分技术引入多层加密机制，在传输过程中对数据进行反复加密，使得任何单层解密都无法获取有效信息，实现数据内容的彻底遮蔽。
通过分布式代理链构建动态传输路径，将单一通信会话分散到多个地理节点与时间片段。利用云基础设施的弹性扩展特性，动态创建和销毁代理节点，使得加密通道的拓扑结构持续变化。这种时空维度上的动态分散策略，将通信特征稀释在广域网络空间与长时间运行过程中，传统基于单点采集的检测系统难以实施有效关联分析。
| ID | Name | Description |
|---|---|---|
| G0016 | APT29 |
APT29 has used multiple layers of encryption within malware to protect C2 communication.[1] |
| G1002 | BITTER | |
| S0631 | Chaes | |
| S0498 | Cryptoistic |
Cryptoistic can engage in encrypted communications with C2.[4] |
| S0367 | Emotet |
Emotet has encrypted data before sending to the C2 server.[5] |
| S0032 | gh0st RAT |
gh0st RAT has encrypted TCP communications to evade detection.[6] |
| C0035 | KV Botnet Activity |
KV Botnet Activity command and control activity includes transmission of an RSA public key in communication from the server, but this is followed by subsequent negotiation stages that represent a form of handshake similar to TLS negotiation.[7] |
| S0681 | Lizar |
Lizar can support encrypted communications between the client and server.[8][9] |
| S1016 | MacMa |
MacMa has used TLS encryption to initialize a custom protocol for C2 communications.[10] |
| G0059 | Magic Hound |
Magic Hound has used an encrypted http proxy in C2 communications.[11] |
| S0198 | NETWIRE | |
| S1012 | PowerLess |
PowerLess can use an encrypted channel for C2 communications.[13] |
| S1046 | PowGoop | |
| S0662 | RCSession |
RCSession can use an encrypted beacon to check in with C2.[15] |
| C0030 | Triton Safety Instrumented System Attack |
In the Triton Safety Instrumented System Attack, TEMP.Veles used cryptcat binaries to encrypt their traffic.[16] |
| G0081 | Tropic Trooper |
Tropic Trooper has encrypted traffic with the C2 to prevent network detection.[17] |
| ID | Mitigation | Description |
|---|---|---|
| M1031 | Network Intrusion Prevention |
Network intrusion detection and prevention systems that use network signatures to identify traffic for specific adversary malware can be used to mitigate activity at the network level. |
| M1020 | SSL/TLS Inspection |
SSL/TLS inspection can be used to see the contents of encrypted sessions to look for network-based indicators of malware communication protocols. |
| ID | Data Source | Data Component | Detects |
|---|---|---|---|
| DS0029 | Network Traffic | Network Traffic Content |
Monitor and analyze traffic patterns and packet inspection associated to protocol(s) that do not follow the expected protocol standards and traffic flows (e.g extraneous packets that do not belong to established flows, gratuitous or anomalous traffic patterns, anomalous syntax, or structure). Consider correlation with process monitoring and command line to detect anomalous processes execution and command line arguments associated to traffic patterns (e.g. monitor anomalies in use of files that do not normally initiate connections for respective protocol(s)). |