FlashNewfunction
YARA-2025-0556
Medium
general
Active
No description available for this rule
FlashNewfunction.yar
Valid Syntax
/*
This Yara ruleset is under the GNU-GPLv2 license (http://www.gnu.org/licenses/gpl-2.0.html) and open to any user or organization, as long as you use it under this license.
*/
rule FlashNewfunction: decodedPDF
{
meta:
ref = "CVE-2010-1297"
hide = true
impact = 5
ref = "http://blog.xanda.org/tag/jsunpack/"
strings:
$unescape = "unescape" fullword nocase
$shellcode = /%u[A-Fa-f0-9]{4}/
$shellcode5 = /(%u[A-Fa-f0-9]{4}){5}/
$cve20101297 = /\/Subtype ?\/Flash/
condition:
($unescape and $shellcode and $cve20101297) or ($shellcode5 and $cve20101297)
}
Rule Metadata
ref
http://blog.xanda.org/tag/jsunpack/
Tags
decodedPDF
String Definitions
{"name":"$unescape","value":"\"unescape\" fullword nocase"}
{"name":"$shellcode","value":"\/%u[A-Fa-f0-9]{4}\/"}
{"name":"$shellcode5","value":"\/(%u[A-Fa-f0-9]{4}){5}\/"}
{"name":"$cve20101297","value":"\/\\\/Subtype ?\\\/Flash\/"}
Threat Analysis
This YARA rule is designed to detect general threats.
Severity Level: Medium
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 FlashNewfunction.yar /path/to/suspicious/file # Scan a directory recursively yara -r FlashNewfunction.yar /path/to/directory/ # Scan with metadata output yara -m FlashNewfunction.yar target_file # Scan process memory (Linux) yara FlashNewfunction.yar /proc/[pid]/exe
Integration Examples
Python (yara-python)
import yara
rules = yara.compile(filepath='FlashNewfunction.yar')
matches = rules.match('/path/to/file')
ClamAV Integration
clamscan --yara-rules=FlashNewfunction.yar /path/to/scan
Rule Information
YARA ID
YARA-2025-0556
Author
Unknown
Repository
Created
August 19, 2025
Last Updated
August 19, 2025
Last Imported
Never
Threat Intelligence
Risk Level
Medium
Category
general
Detection Confidence
Analysis Pending
False Positive Rate
Not Available
Last Seen in Wild
No Data
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