Justin Ibarra
59da2da474
* add unit tests to ensure host type and platform are included * add host.os.name 'linux' to all linux rules * add host.os.name macos to mac rules * add host.os.name to windows rules; fix linux dates * update from host.os.name to host.os.type Co-authored-by: brokensound77 <brokensound77@users.noreply.github.com> Co-authored-by: Jonhnathan <26856693+w0rk3r@users.noreply.github.com>
89 lines
2.9 KiB
TOML
89 lines
2.9 KiB
TOML
[metadata]
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creation_date = "2021/10/05"
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integration = ["endpoint"]
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maturity = "production"
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min_stack_comments = "New fields added: required_fields, related_integrations, setup"
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min_stack_version = "8.3.0"
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updated_date = "2023/02/22"
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[rule]
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author = ["Elastic"]
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description = """
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Identifies when a screensaver plist file is modified by an unexpected process. An adversary can maintain persistence on
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a macOS endpoint by creating a malicious screensaver (.saver) file and configuring the screensaver plist file to execute
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code each time the screensaver is activated.
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"""
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from = "now-9m"
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index = ["auditbeat-*", "logs-endpoint.events.*"]
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language = "eql"
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license = "Elastic License v2"
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name = "Screensaver Plist File Modified by Unexpected Process"
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note = """## Triage and analysis
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- Analyze the plist file modification event to identify whether the change was expected or not
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- Investigate the process that modified the plist file for malicious code or other suspicious behavior
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- Identify if any suspicious or known malicious screensaver (.saver) files were recently written to or modified on the host
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## Setup
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If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2, events will not define `event.ingested` and default fallback for EQL rules was not added until 8.2, so you will need to add a custom pipeline to populate `event.ingested` to @timestamp for this rule to work.
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"""
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references = [
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"https://posts.specterops.io/saving-your-access-d562bf5bf90b",
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"https://github.com/D00MFist/PersistentJXA",
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]
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risk_score = 47
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rule_id = "e6e8912f-283f-4d0d-8442-e0dcaf49944b"
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severity = "medium"
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tags = ["Elastic", "Host", "macOS", "Threat Detection", "Persistence"]
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timestamp_override = "event.ingested"
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type = "eql"
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query = '''
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file where host.os.type == "macos" and event.type != "deletion" and
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file.name: "com.apple.screensaver.*.plist" and
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file.path : (
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"/Users/*/Library/Preferences/ByHost/*",
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"/Library/Managed Preferences/*",
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"/System/Library/Preferences/*"
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) and
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(
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process.code_signature.trusted == false or
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process.code_signature.exists == false or
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/* common script interpreters and abused native macOS bins */
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process.name : (
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"curl",
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"mktemp",
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"tail",
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"funzip",
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"python*",
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"osascript",
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"perl"
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)
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) and
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/* Filter OS processes modifying screensaver plist files */
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not process.executable : (
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"/usr/sbin/cfprefsd",
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"/usr/libexec/xpcproxy",
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"/System/Library/CoreServices/ManagedClient.app/Contents/Resources/MCXCompositor",
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"/System/Library/CoreServices/ManagedClient.app/Contents/MacOS/ManagedClient"
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)
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'''
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[[rule.threat]]
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framework = "MITRE ATT&CK"
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[[rule.threat.technique]]
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id = "T1546"
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name = "Event Triggered Execution"
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reference = "https://attack.mitre.org/techniques/T1546/"
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[rule.threat.tactic]
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id = "TA0003"
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name = "Persistence"
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reference = "https://attack.mitre.org/tactics/TA0003/"
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