Detection Strategy of Transmitted Data Manipulation

ID: DET0254
Domains: Enterprise
Analytics: AN0702, AN0703, AN0704
Version: 1.0
Created: 21 October 2025
Last Modified: 21 October 2025

Analytics

AN0702

Monitor for anomalies in transmitted data streams, including mismatched file integrity checks, API interception, or man-in-the-middle modifications. Detect unexpected use of APIs that handle network I/O where transmitted data integrity could be manipulated.

Log Sources
Data Component Name Channel
Network Connection Creation (DC0082) WinEventLog:Sysmon EventCode=3
File Metadata (DC0059) WinEventLog:Sysmon EventCode=15
Mutable Elements
Field Description
IntegrityBaseline Hash baselines or digital signature references to validate transmitted data.
MonitoredPorts List of ports/services where data integrity validation is enforced.

AN0703

Detect alterations of transmitted data via monitoring syscalls (send, recv, write) or middleware interception. Identify mismatched file hashes when compared at origin vs. destination. Watch for anomalous activity from processes interacting with secure transmission services (e.g., OpenSSL, scp).

Log Sources
Data Component Name Channel
OS API Execution (DC0021) auditd:SYSCALL send, recv, write: Abnormal interception or alteration of transmitted data
Network Traffic Content (DC0085) linux:syslog Integrity mismatch warnings or malformed packets detected
Mutable Elements
Field Description
WatchedProcesses List of processes authorized to handle transmitted data (e.g., sshd, nginx).
HashCheckInterval Frequency of out-of-band integrity verification checks.

AN0704

Monitor system APIs such as CFNetwork and SecureTransport for anomalies in transmitted data streams. Detect mismatches in file hashes or SSL/TLS downgrade attempts that enable manipulation of transmitted data.

Log Sources
Data Component Name Channel
Network Traffic Flow (DC0078) macos:unifiedlog Suspicious anomalies in transmitted data integrity during application network operations
OS API Execution (DC0021) macos:osquery CALCULATE: Integrity validation of transmitted data via hash checks
Mutable Elements
Field Description
TLSValidationRules Custom rules for enforcing HTTPS/TLS integrity checks to prevent downgrade manipulation.
AllowedApps Whitelisted macOS apps permitted to transmit critical data.