Environmental Keying Discovery-to-Decryption Behavioral Chain Detection Strategy

ID: DET0474
Domains: Enterprise
Analytics: AN1305, AN1306, AN1307
Version: 1.0
Created: 21 October 2025
Last Modified: 21 October 2025

Analytics

AN1305

Windows-specific environmental keying behavioral chain: (1) Rapid system information discovery through multiple techniques (WMI queries, registry enumeration, network share discovery, hostname/domain checks), (2) Target validation through specific environmental artifact collection (AD domain membership, network topology, installed software versions), (3) Cryptographic operation correlation indicating payload decryption based on collected environmental values, (4) Subsequent malicious code execution following successful environmental validation, (5) Temporal clustering of discovery activities suggesting automated environmental assessment

Log Sources
Data Component Name Channel
Logon Session Creation (DC0067) WinEventLog:Security EventCode=4624,4648, 4672
Process Creation (DC0032) WinEventLog:Sysmon EventCode=1
Network Connection Creation (DC0082) WinEventLog:Sysmon EventCode=3
Module Load (DC0016) WinEventLog:Sysmon EventCode=7
Process Access (DC0035) WinEventLog:Sysmon EventCode=25
WMI Creation (DC0008) WinEventLog:WMI EventCode=5857, 5860, 5861
Command Execution (DC0064) WinEventLog:PowerShell EventCode=4103
Mutable Elements
Field Description
DiscoveryTimeWindow Time window for correlating multiple discovery activities as part of environmental assessment - adjust based on observed attack patterns and system performance (default: 300 seconds)
CriticalDiscoveryThreshold Minimum number of distinct discovery techniques within time window to trigger detection - tune based on environment's normal administrative activity levels
TargetSpecificArtifacts Organization-specific environmental elements that adversaries might target (domain names, network shares, specific hostnames, software versions)
CryptographicIndicatorPatterns Process names, command lines, and API calls indicating potential decryption operations - customize based on observed cryptographic tool usage in environment
LegitimateAdminAccounts User accounts authorized to perform extensive system discovery - maintain current list to reduce false positives from legitimate administrative activities
BusinessHoursBaseline Normal business hours for risk scoring adjustment - discovery activities outside these hours receive higher risk scores
WMIQueryComplexityThreshold Complexity metric for WMI queries to identify sophisticated environmental assessment versus simple system checks

AN1306

Linux environmental keying behavioral chain: (1) System information gathering through native commands (uname, hostname, id, whoami, ifconfig/ip) and file system enumeration, (2) Network configuration discovery (route tables, DNS settings, network interfaces), (3) Filesystem and mount point analysis for target-specific directories or devices, (4) Process and service enumeration to identify target-specific software, (5) Cryptographic library usage correlation with collected environmental data, (6) Payload execution following successful environmental validation

Log Sources
Data Component Name Channel
Command Execution (DC0064) auditd:SYSCALL execve syscalls for discovery commands (uname, hostname, id, whoami, ps, netstat, mount) with command-line parameter analysis
File Access (DC0055) linux:syslog kernel messages related to cryptographic operations, module loading, and filesystem access patterns
Process Creation (DC0032) linux:osquery process_events
Mutable Elements
Field Description
DiscoveryCommandSequenceThreshold Number of distinct discovery commands within time window to trigger detection - adjust based on normal system administration patterns in environment
ProcessAncestryDepth Depth of process parent-child relationships to analyze for discovery activity clustering - balance between detection efficacy and performance
CryptographicLibraryIndicators Shared libraries and system calls indicating cryptographic operations (libcrypto, libssl, openssl) - customize based on environment-specific crypto tools
TargetSpecificFilesystems Organization-specific mount points, network filesystems, or device paths that adversaries might validate against
AuthorizedDiscoveryUsers User accounts and service accounts authorized for extensive system discovery operations - maintain for false positive reduction
NetworkConfigurationBaseline Normal network interface configurations and routing tables to identify anomalous network discovery patterns
ContainerContextIdentifiers Container runtime identifiers and namespace patterns to detect environmental assessment targeting container environments

AN1307

macOS environmental keying behavioral chain: (1) System information discovery through native utilities (system_profiler, sw_vers, hostname, dscl) and Security framework queries, (2) Hardware and software enumeration including serial numbers, installed applications, and system versions, (3) Network configuration assessment (networksetup, scutil) and wireless network discovery, (4) Keychain and security context validation, (5) Unified Logs correlation with cryptographic framework usage (CommonCrypto, Security.framework), (6) Application bundle execution following environmental validation

Log Sources
Data Component Name Channel
Process Creation (DC0032) macos:unifiedlog process execution events for discovery utilities (system_profiler, sw_vers, dscl, networksetup) with command-line parameter analysis
Command Execution (DC0064) macos:unifiedlog Security framework operations including keychain access, cryptographic operations, and certificate validation
File Access (DC0055) fs:fsevents file system events indicating access to system configuration files and environmental information sources
Mutable Elements
Field Description
SystemProfilerDataTypes Specific system_profiler data types that adversaries commonly target (SPHardwareDataType, SPSoftwareDataType, SPNetworkDataType) - customize based on threat intelligence
SecurityFrameworkOperationPatterns Security.framework and CommonCrypto API usage patterns indicating cryptographic operations for environmental keying
UnifiedLogRetentionWindow Time window for correlating discovery activities with subsequent cryptographic operations - balance between detection coverage and log volume
ApplicationBundleValidationPaths Specific application bundle paths and identifiers that might be subject to environmental validation
NetworkConfigurationIdentifiers Organization-specific network configurations, WiFi SSIDs, and network services that adversaries might validate against
MacOSVersionBaseline Expected macOS versions and configurations in environment to identify version-specific environmental targeting
FSEventsFilteringCriteria File system event filtering criteria to focus on security-relevant file access patterns while managing event volume