PowerShell Suspicious Payload Encoded and Compressed
Identifies PowerShell script block content that combines Base64 decoding with .NET decompression (Deflate/GZip). Attackers use this pattern to deobfuscate and reconstruct payloads in memory to evade defenses.
Detection logic
Its licence does not clear it for publishing here
Sunturai publishes a detection's own text where the licence it arrived under has been reviewed and permits it, and Elastic License 2.0 has not. The query as its source wrote it, its canonical form and the hash that pins this revision are in the workspace record.
Detection requirements
- Platform
- ContainersESXiIaaSIdentity ProviderLinuxmacOSNetwork DevicesOffice SuiteSaaSWindows
The rule states no platform. This is derived from the 3 ATT&CK techniques it maps to.
- Log source category
- event_index
Known benign triggers
- Legitimate PowerShell scripts that reconstruct to a confirmed benign installer, updater, or administrative workflow for the same user and host scope.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
No references are available for this detection.
From the source
- At source
- Open at source
- Upstream identifier
- 81fe9dc6-a2d7-4192-a2d8-eed98afc766a
- Tagged by the source as
- Data Source: PowerShell LogsDomain: EndpointNoise: MediumOS: WindowsPerformance: NormalPlatform: WindowsProfile: RecommendedResources: Investigation GuideRule Type: Custom Query (KQL)Tactic: Defense EvasionThreat: Script-Based ExecutionUse Case: Threat Detection
Licence
- Published under
- Elastic License 2.0Read the licence
- Attribution
- Required
Authorship
- Written by
- Published
- Sep 20, 2026
- Version
- 3