Detectionmediumtest

New File Exclusion Added To Time Machine Via Tmutil - MacOS

Detects the addition of a new file or path exclusion to MacOS Time Machine via the "tmutil" utility. An adversary could exclude a path from Time Machine backups to prevent certain files from being backed up.

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Launch
Pratinav ChandraCreated Wed May 299acf45ed-3a26-4062-bf08-56857613eb52macos
Log Source
macOSProcess Creation
ProductmacOS← raw: macos
CategoryProcess Creation← raw: process_creation

Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.

Detection Logic
Detection Logic2 selectors
detection:
    selection_img:
        - Image|endswith: '/tmutil'
        - CommandLine|contains: 'tmutil'
    selection_cmd:
        CommandLine|contains: 'addexclusion'
    condition: all of selection_*
False Positives

Legitimate administrator activity

Rule Metadata
Rule ID
9acf45ed-3a26-4062-bf08-56857613eb52
Status
test
Level
medium
Type
Detection
Created
Wed May 29
Path
rules/macos/process_creation/proc_creation_macos_tmutil_exclude_file_from_backup.yml
Raw Tags
attack.impactattack.t1490
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