自动化渗出指攻击者通过预设脚本或程序自动执行数据窃取与传输的过程,通常与数据收集阶段紧密衔接。该技术利用程序化操作实现高效持续的数据渗出,常通过命令控制信道(C2)或替代协议(如DNS、HTTP)进行传输。防御方可通过监控异常文件访问模式(如非业务进程遍历多目录)、检测非常规网络连接(如内部主机与未知外部端点持续通信)等手段进行识别,并采用数据流分析识别未授权传输行为。
为规避传统自动化渗出技术因数据量大、传输连续性强而易于被检测的缺陷,攻击者发展出多维度的隐蔽渗出技术,通过数据形态重构、协议深度伪装及时序智能调控等策略,将渗出行为解构为符合业务特征的微观数据流,在维持渗出效率的同时实现"数据即服务"的隐匿传输。
现有自动化渗出匿迹技术的核心逻辑聚焦于数据生命周期与网络行为的特征重构。攻击者通过分片混淆技术将数据原子化,破坏完整性检测条件;利用协议隧道化实现传输层合规性伪装,规避协议异常检测;借助低频时序控制融合业务流量节奏,消除行为异常性。三类技术的共性在于突破传统渗出行为的大流量、高连续性特征,通过数据微分化、协议标准化及时序自然化的协同作用,使每个渗出单元在数据形态、传输方式和时间分布等维度均符合合法业务特征。分片混淆渗出侧重数据本身的不可识别性,协议隧道化确保传输通道的合法性证明,低频时序控制则从行为模式层面实现隐匿,三者共同构建出"微观合规、宏观不可察"的新型渗出范式。
匿迹技术的演进导致传统基于流量阈值告警、协议合规检查的防御体系面临严峻挑战,防御方需构建细粒度数据流图谱分析能力,结合协议行为建模与上下文感知检测技术,实现渗出行为的跨协议关联识别,并引入数据血缘追踪机制应对分片混淆攻击。
| 效应类型 | 是否存在 |
|---|---|
| 特征伪装 | ✅ |
| 行为透明 | ❌ |
| 数据遮蔽 | ✅ |
| 时空释痕 | ✅ |
攻击者通过深度协议仿真技术将渗出流量伪装成合法业务交互。例如利用标准HTTPS协议封装渗出数据,严格遵循TLS握手规范与HTTP头部格式,使流量在协议特征层面与正常Web服务完全一致。或通过模仿数据库备份服务的TCP窗口管理策略,使渗出流量在传输控制层面呈现合法特征。
采用多层加密与编码机制对渗出数据进行遮蔽,包括应用层AES-GCM加密、传输层TLS 1.3保护以及自定义二进制编码方案。部分技术结合区块链智能合约实现数据分片加密存储,确保单一片段无法还原有效信息。
通过低频时序控制与全球节点协同,将集中式渗出任务分解为长周期、低强度的离散操作。利用云函数等临时计算资源动态切换渗出端点,使单次行为特征低于检测阈值,整体攻击指纹被稀释在业务流量时间序列中。
| ID | Name | Description |
|---|---|---|
| S0438 | Attor |
Attor has a file uploader plugin that automatically exfiltrates the collected data and log files to the C2 server.[1] |
| S0050 | CosmicDuke |
CosmicDuke exfiltrates collected files automatically over FTP to remote servers.[2] |
| S0538 | Crutch |
Crutch has automatically exfiltrated stolen files to Dropbox.[3] |
| S0600 | Doki |
Doki has used a script that gathers information from a hardcoded list of IP addresses and uploads to an Ngrok URL.[4] |
| S0377 | Ebury |
If credentials are not collected for two weeks, Ebury encrypts the credentials using a public key and sends them via UDP to an IP address located in the DNS TXT record.[5][6] |
| S0363 | Empire |
Empire has the ability to automatically send collected data back to the threat actors' C2.[7] |
| C0001 | Frankenstein |
During Frankenstein, the threat actors collected information via Empire, which was automatically sent back to the adversary's C2.[7] |
| G0047 | Gamaredon Group |
Gamaredon Group has used modules that automatically upload gathered documents to the C2 server.[8] |
| G0004 | Ke3chang |
Ke3chang has performed frequent and scheduled data exfiltration from compromised networks.[9] |
| S0395 | LightNeuron |
LightNeuron can be configured to automatically exfiltrate files under a specified directory.[10] |
| S0409 | Machete |
Machete’s collected files are exfiltrated automatically to remote servers.[11] |
| S1017 | OutSteel |
OutSteel can automatically upload collected files to its C2 server.[12] |
| S0643 | Peppy |
Peppy has the ability to automatically exfiltrate files and keylogs.[13] |
| S1148 | Raccoon Stealer |
Raccoon Stealer will automatically collect and exfiltrate data identified in received configuration files from command and control nodes.[14][15][16] |
| G1039 | RedCurl | |
| S0090 | Rover |
Rover automatically searches for files on local drives based on a predefined list of file extensions and sends them to the command and control server every 60 minutes. Rover also automatically sends keylogger files and screenshots to the C2 server on a regular timeframe.[19] |
| S0445 | ShimRatReporter |
ShimRatReporter sent collected system and network information compiled into a report to an adversary-controlled C2.[20] |
| G0121 | Sidewinder |
Sidewinder has configured tools to automatically send collected files to attacker controlled servers.[21] |
| S0491 | StrongPity |
StrongPity can automatically exfiltrate collected documents to the C2 server.[22][23] |
| S0467 | TajMahal |
TajMahal has the ability to manage an automated queue of egress files and commands sent to its C2.[24] |
| S0131 | TINYTYPHON |
When a document is found matching one of the extensions in the configuration, TINYTYPHON uploads it to the C2 server.[25] |
| G0081 | Tropic Trooper |
Tropic Trooper has used a copy function to automatically exfiltrate sensitive data from air-gapped systems using USB storage.[26] |
| S0136 | USBStealer |
USBStealer automatically exfiltrates collected files via removable media when an infected device connects to an air-gapped victim machine after initially being connected to an internet-enabled victim machine. [27] |
| G1035 | Winter Vivern |
Winter Vivern delivered a PowerShell script capable of recursively scanning victim machines looking for various file types before exfiltrating identified files via HTTP.[28] |
This type of attack technique cannot be easily mitigated with preventive controls since it is based on the abuse of system features.
| ID | Data Source | Data Component | Detects |
|---|---|---|---|
| DS0017 | Command | Command Execution |
Monitor executed commands and arguments that may exfiltrate data, such as sensitive documents, through the use of automated processing after being gathered during Collection |
| DS0022 | File | File Access |
Monitor for abnormal access to files (i.e. .pdf, .docx, .jpg, etc.), especially sensitive documents, through the use of automated processing after being gathered during Collection. |
| DS0029 | Network Traffic | Network Connection Creation |
Monitor for newly constructed network connections associated with processes performing collection activity, especially those involving abnormal/untrusted hosts. |
| Network Traffic Content |
Monitor network traffic content for evidence of data exfiltration, such as gratuitous or anomalous outbound traffic containing collected data. Consider correlation with process monitoring and command lines associated with collection and exfiltration. |
||
| Network Traffic Flow |
Monitor and analyze network flows 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, or gratuitous or anomalous traffic patterns). Consider analyzing newly constructed network connections that are sent or received by untrusted hosts, unexpected hardware devices, or other uncommon data flows. |
||
| DS0012 | Script | Script Execution |
Monitor for any attempts to enable scripts running on a system would be considered suspicious. If scripts are not commonly used on a system, but enabled, scripts running out of cycle from patching or other administrator functions are suspicious. Scripts should be captured from the file system when possible to determine their actions and intent. |