cyberstrikeus T1481 Web Service
High-Level Description
Adversaries may use an existing, legitimate external Web service as a means for relaying data to/from a compromised system. Popular websites and social media, acting as a mechanism for C2, may give a significant amount of cover. This is due to the likelihood that hosts within a network are already communicating with them prior to a compromise. Using common services, such as those offered by Google or Twitter, makes it easier for adversaries to hide in expected noise. Web service providers commonly use SSL/TLS encryption, giving adversaries an added level of protection.
Use of Web services may also protect back-end C2 infrastructure from discovery through malware binary analysis, or enable operational resiliency (since this infrastructure may be dynamically changed).
Kill Chain Phase
- Command and Control (TA0037)
Platforms: Android, iOS
What to Check
- Identify if Web Service technique is applicable to target mobile environment
- Check Android devices for indicators of Web Service
- Check iOS devices for indicators of Web Service
- Assess detection coverage (1 detection strategies)
How to Test
Identify Attack Surface
Determine if the target mobile environment is susceptible to Web Service by examining the target platforms (Android, iOS).
Assess Existing Defenses
Review whether mitigations for T1481 are in place. If defenses are absent or misconfigured, this technique may be exploitable.
Remediation Guide
No specific mitigations documented for this technique.
Detection
Detection of Web Service
Risk Assessment
| Finding | Severity | Impact |
|---|---|---|
| Web Service technique applicable | Medium | Command And Control |
CWE Categories
| CWE ID | Title |
|---|---|
| CWE-300 | Channel Accessible by Non-Endpoint |