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will be released for this version. For the latest information, see the
current release documentation.
Unsigned DLL Side-Loading from a Suspicious Folderedit
Identifies a Windows trusted program running from locations often abused by adversaries to masquerade as a trusted program and loading a recently dropped DLL. This behavior may indicate an attempt to evade defenses via side-loading a malicious DLL within the memory space of a signed processes.
Rule type: eql
Rule indices:
- logs-endpoint.events.*
Severity: medium
Risk score: 47
Runs every: 5m
Searches indices from: now-9m (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
References: None
Tags:
- Elastic
- Host
- Windows
- Threat Detection
- Defense Evasion
Version: 1
Rule authors:
- Elastic
Rule license: Elastic License v2
Investigation guideedit
Rule queryedit
library where
process.code_signature.trusted == true and
(dll.Ext.relative_file_creation_time <= 500 or dll.Ext.relative_file_name_modify_time <= 500) and
not dll.code_signature.status : ("trusted", "errorExpired", "errorCode_endpoint*", "errorChaining") and
/* Suspicious Paths */
dll.path : ("?:\\PerfLogs\\*.dll",
"?:\\Users\\*\\Pictures\\*.dll",
"?:\\Users\\*\\Music\\*.dll",
"?:\\Users\\Public\\*.dll",
"?:\\Users\\*\\Documents\\*.dll",
"?:\\Windows\\Tasks\\*.dll",
"?:\\Windows\\System32\\Tasks\\*.dll",
"?:\\Intel\\*.dll",
"?:\\AMD\\Temp\\*.dll",
"?:\\Windows\\AppReadiness\\*.dll",
"?:\\Windows\\ServiceState\\*.dll",
"?:\\Windows\\security\\*.dll",
"?:\\Windows\\System\\*.dll",
"?:\\Windows\\IdentityCRL\\*.dll",
"?:\\Windows\\Branding\\*.dll",
"?:\\Windows\\csc\\*.dll",
"?:\\Windows\\DigitalLocker\\*.dll",
"?:\\Windows\\en-US\\*.dll",
"?:\\Windows\\wlansvc\\*.dll",
"?:\\Windows\\Prefetch\\*.dll",
"?:\\Windows\\Fonts\\*.dll",
"?:\\Windows\\diagnostics\\*.dll",
"?:\\Windows\\TAPI\\*.dll",
"?:\\Windows\\INF\\*.dll",
"?:\\windows\\tracing\\*.dll",
"?:\\windows\\IME\\*.dll",
"?:\\Windows\\Performance\\*.dll",
"?:\\windows\\intel\\*.dll",
"?:\\windows\\ms\\*.dll",
"?:\\Windows\\dot3svc\\*.dll",
"?:\\Windows\\ServiceProfiles\\*.dll",
"?:\\Windows\\panther\\*.dll",
"?:\\Windows\\RemotePackages\\*.dll",
"?:\\Windows\\OCR\\*.dll",
"?:\\Windows\\appcompat\\*.dll",
"?:\\Windows\\apppatch\\*.dll",
"?:\\Windows\\addins\\*.dll",
"?:\\Windows\\Setup\\*.dll",
"?:\\Windows\\Help\\*.dll",
"?:\\Windows\\SKB\\*.dll",
"?:\\Windows\\Vss\\*.dll",
"?:\\Windows\\Web\\*.dll",
"?:\\Windows\\servicing\\*.dll",
"?:\\Windows\\CbsTemp\\*.dll",
"?:\\Windows\\Logs\\*.dll",
"?:\\Windows\\WaaS\\*.dll",
"?:\\Windows\\twain_32\\*.dll",
"?:\\Windows\\ShellExperiences\\*.dll",
"?:\\Windows\\ShellComponents\\*.dll",
"?:\\Windows\\PLA\\*.dll",
"?:\\Windows\\Migration\\*.dll",
"?:\\Windows\\debug\\*.dll",
"?:\\Windows\\Cursors\\*.dll",
"?:\\Windows\\Containers\\*.dll",
"?:\\Windows\\Boot\\*.dll",
"?:\\Windows\\bcastdvr\\*.dll",
"?:\\Windows\\TextInput\\*.dll",
"?:\\Windows\\schemas\\*.dll",
"?:\\Windows\\SchCache\\*.dll",
"?:\\Windows\\Resources\\*.dll",
"?:\\Windows\\rescache\\*.dll",
"?:\\Windows\\Provisioning\\*.dll",
"?:\\Windows\\PrintDialog\\*.dll",
"?:\\Windows\\PolicyDefinitions\\*.dll",
"?:\\Windows\\media\\*.dll",
"?:\\Windows\\Globalization\\*.dll",
"?:\\Windows\\L2Schemas\\*.dll",
"?:\\Windows\\LiveKernelReports\\*.dll",
"?:\\Windows\\ModemLogs\\*.dll",
"?:\\Windows\\ImmersiveControlPanel\\*.dll",
"?:\\$Recycle.Bin\\*.dll") and
/* DLL loaded from the process.executable current directory */
endswith~(substring(dll.path, 0, length(dll.path) - (length(dll.name) + 1)), substring(process.executable, 0, length(process.executable) - (length(process.name) + 1)))
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Defense Evasion
- ID: TA0005
- Reference URL: https://attack.mitre.org/tactics/TA0005/
-
Technique:
- Name: Hijack Execution Flow
- ID: T1574
- Reference URL: https://attack.mitre.org/techniques/T1574/
-
Sub-technique:
- Name: DLL Side-Loading
- ID: T1574.002
- Reference URL: https://attack.mitre.org/techniques/T1574/002/