Adversaries may gain access and continuously communicate with victims by injecting malicious content into systems through online network traffic. Rather than luring victims to malicious payloads hosted on a compromised website (i.e., Drive-by Target followed by Drive-by Compromise), adversaries may initially access victims through compromised data-transfer channels where they can manipulate traffic and/or inject their own content. These compromised online network channels may also be used to deliver additional payloads (i.e., Ingress Tool Transfer) and other data to already compromised systems.(Citation: ESET MoustachedBouncer)
Adversaries may inject content to victim systems in various ways, including:
Content injection is often the result of compromised upstream communication channels, for example at the level of an internet service provider (ISP) as is the case with "lawful interception."(Citation: Kaspersky ManOnTheSide)(Citation: ESET MoustachedBouncer)(Citation: EFF China GitHub Attack)
Detection Strategy for Content Injection
Restrict Web-Based Content: Restricting web-based content involves enforcing policies and technologies that limit access to potentially malicious websites, unsafe downloads, and unauthorized browser behaviors. This can include URL filtering, download restrictions, script blocking, and extension control to protect against exploitation, phishing, and malware delivery. This mitigation can be implemented through the following measures:
Deploy Web Proxy Filtering:
Enable DNS-Based Filtering:
Enforce Content Security Policies (CSP):
Control Browser Features:
Monitor and Alert on Web-Based Threats:
Encrypt Sensitive Information: Protect sensitive information at rest, in transit, and during processing by using strong encryption algorithms. Encryption ensures the confidentiality and integrity of data, preventing unauthorized access or tampering. This mitigation can be implemented through the following measures:
Encrypt Data at Rest:
Encrypt Data in Transit:
Encrypt Backups:
Encrypt Application Secrets:
Database Encryption:
No cross-framework mappings available