Detection of Tainted Content Written to Shared Storage

Technique Detected:  Taint Shared Content | T1080

ID: DET0471
Domains: Enterprise
Analytics: AN1298, AN1299, AN1300, AN1301, AN1302
Version: 1.0
Created: 21 October 2025
Last Modified: 21 October 2025

Analytics

AN1298

Detects adversary tampering of shared directories via file drops (e.g., malicious LNK, EXE, VBS) followed by user execution or suspicious network activity.

Log Sources
Data Component Name Channel
File Creation (DC0039) WinEventLog:Sysmon EventCode=11
Network Share Access (DC0102) WinEventLog:Security EventCode=5145
Mutable Elements
Field Description
SharedPathPrefix Defines monitored shared directories (e.g., \\server\HR\).
ExecutableExtensions Monitored file types dropped in shared paths (e.g., .lnk, .exe, .vbs).

AN1299

Detects script or binary modification within shared NFS/SMB directories followed by process execution from those paths.

Log Sources
Data Component Name Channel
File Modification (DC0061) auditd:SYSCALL write
Network Share Access (DC0102) NSM:Flow smb_files.log
Mutable Elements
Field Description
MountPath Mount path of monitored shared volumes (e.g., /mnt/shared).
FilenamePattern Pattern matching of abnormal or disguised filenames.

AN1300

Detects modification of shared network folders via .app bundles or scripting files with hidden extensions (e.g., double extensions like docx.app).

Log Sources
Data Component Name Channel
File Creation (DC0039) fs:fsevents Directory events (kFSEventStreamEventFlagItemCreated)
File Modification (DC0061) macos:unifiedlog file writes
Mutable Elements
Field Description
FileExtensionDeception Monitors use of hidden extensions or double extensions.
TargetSharedFolder Defines sensitive shared folders (e.g., /Users/Shared/HR).

AN1301

Detects upload of malicious or unusual file types into cloud-shared folders, followed by user downloads or interactions.

Log Sources
Data Component Name Channel
File Creation (DC0039) gcp:workspaceaudit drive.activity logs
Network Share Access (DC0102) m365:unified FileUploaded, FileAccessed
Mutable Elements
Field Description
UserUploadRateThreshold Abnormal upload patterns into shared drives.
MaliciousFileIndicator File hash or known-bad filename pattern matching.

AN1302

Detects embedded macros or scripts added to shared documents or use of external references to execute code.

Log Sources
Data Component Name Channel
File Modification (DC0061) m365:defender OfficeTelemetry or DLP
Mutable Elements
Field Description
MacroExecutionPolicy Controls macro execution based on user or group policy.
SuspiciousKeywordMatch Regex match on suspicious VBA function names or calls.