Roshal Archive (RAR) or PowerShell File Downloaded from the Internet
Detects a Roshal Archive (RAR) file or PowerShell script downloaded from the internet by an internal host. Gaining initial access to a system and then downloading encoded or encrypted tools to move laterally is a…
Description
Detects a Roshal Archive (RAR) file or PowerShell script downloaded from the internet by an internal host. Gaining initial access to a system and then downloading encoded or encrypted tools to move laterally is a common practice for adversaries as a way to protect their more valuable tools and tactics, techniques, and procedures (TTPs). This may be atypical behavior for a managed network and can be indicative of malware, exfiltration, or command and control.
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
- ESXiLinuxmacOSNetwork DevicesWindows
The rule states no platform. This is derived from the ATT&CK technique it maps to.
- Log source category
- event_index
Known benign triggers
- Downloading RAR or PowerShell files from the Internet may be expected for certain systems. This rule should be tailored to either exclude systems as sources or destinations in which this behavior is expected.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| cloud.google.com/blog/topics/threat-intelligence/fin7-phishing-lnk | 3 |
| www.iana.org/assignments/iana-ipv4-special-registry/iana-ipv4-special-registry.xhtml | 20 |
| www.justice.gov/opa/press-release/file/1084361/download | Only this detection cites it |
From the source
- At source
- Open at source
- Upstream identifier
- ff013cb4-274d-434a-96bb-fe15ddd3ae92
- Tagged by the source as
- Data Source: FortinetData Source: Network Packet CaptureData Source: PAN-OSDomain: EndpointDomain: NetworkNoise: MediumPerformance: NormalProfile: RecommendedResources: Investigation GuideRule Type: Custom Query (KQL)Tactic: Command and ControlThreat: Script-Based ExecutionUse Case: Threat Detection
Licence
- Published under
- Elastic License 2.0Read the licence
- Attribution
- Required
Authorship
- Written by
- Published
- Oct 8, 2026
- Version
- 5