BackdoorWin32FynloskiASample
YARA-2025-1984
High
general
Active
No description available for this rule
BackdoorWin32FynloskiASample.yar
Valid Syntax
rule BackdoorWin32FynloskiASample
{
meta:
Description = "Backdoor.Fynloski.sm"
ThreatLevel = "5"
strings:
$ = "#BOT#VisitUrl" ascii wide
$ = "#BOT#OpenUrl" ascii wide
$ = "#BOT#Ping" ascii wide
$ = "BTRESULTPing|Res" ascii wide
$ = "#BOT#RunPrompt" ascii wide
$ = "BTRESULTClose" ascii wide
$ = "#BOT#SvrUninstal" ascii wide
$ = "#BOT#URLUpdate" ascii wide
$ = "BTERRORUpdate" ascii wide
$ = "BTRESULTUpdate" ascii wide
$ = "#BOT#URLDownload" ascii wide
$ = "BTRESULTOpen" ascii wide
$ = "BTERRORDownload" ascii wide
$ = "BTRESULTDownload" ascii wide
$ = "BTRESULTMass" ascii wide
$ = "BTRESULTHTTP" ascii wide
$ = "BTERRORVisit" ascii wide
$ = "BTRESULTSyn" ascii wide
$ = "BTRESULTUDP" ascii wide
$ = "Flood|UDP Flood task finished" ascii wide
$ = "Flood|Syn task finished" ascii wide
$ = "Flood|Http Flood task finished" ascii wide
condition:
3 of them
}Rule Metadata
Description
Backdoor.Fynloski.sm
ThreatLevel
5
Threat Analysis
This YARA rule is designed to detect general threats.
Severity Level: High
The rule uses pattern matching to identify specific byte sequences, strings, or behavioral patterns associated with malicious activity.
Detection Capabilities
- File-based detection for executables and documents
- Memory scanning for running processes
- Network traffic analysis support
Command Line Usage
# Scan a single file yara BackdoorWin32FynloskiASample.yar /path/to/suspicious/file # Scan a directory recursively yara -r BackdoorWin32FynloskiASample.yar /path/to/directory/ # Scan with metadata output yara -m BackdoorWin32FynloskiASample.yar target_file # Scan process memory (Linux) yara BackdoorWin32FynloskiASample.yar /proc/[pid]/exe
Integration Examples
Python (yara-python)
import yara
rules = yara.compile(filepath='BackdoorWin32FynloskiASample.yar')
matches = rules.match('/path/to/file')
ClamAV Integration
clamscan --yara-rules=BackdoorWin32FynloskiASample.yar /path/to/scan
Rule Information
YARA ID
YARA-2025-1984
Author
Unknown
Repository
Created
August 19, 2025
Last Updated
August 19, 2025
Last Imported
Never
Threat Intelligence
Risk Level
High
Category
general
Detection Confidence
Analysis Pending
False Positive Rate
Not Available
Last Seen in Wild
No Data
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