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Just adjust or omit below two strings for next version they code :) @unixfreaxjp

yara LOW Yara-Rules
community
This rule was pulled from an open-source repository and enriched with AI. Validate in a test environment before deploying to production.
View original rule at Yara-Rules →
Retrieved: 2026-06-28T23:00:00Z · Confidence: medium

Hunt Hypothesis

This hunt targets potential misconfigurations or placeholder artifacts in Azure Sentinel where legacy code comments or test strings persist in production environments, indicating a lack of rigorous change management. Proactively hunting for these anomalies allows the SOC team to reduce alert noise and identify opportunities to harden their detection logic before such artifacts obscure critical security signals.

YARA Rule

rule MALW_Rebirth_Vulcan_ELF {
	meta:
		description = "Detects Rebirth Vulcan variant a torlus NextGen MALW"
		description = "Just adjust or omit below two strings for next version they code :) @unixfreaxjp"
		date = "2018-01-21"
	strings:
                $spec01 = "vulcan.sh" fullword nocase wide ascii
		$spec02 = "Vulcan" fullword nocase wide ascii
	condition:
                all of them
		and is__elf
		and is__str_Rebirth_gen3
		and is__hex_Rebirth_gen3
		and is__bot_Rebirth_gen3
		and filesize < 300KB 
}

Deployment Notes

This YARA rule can be deployed in the following contexts:

This rule contains 2 string patterns in its detection logic.

False Positive Guidance

Based on the detection rule title and logic provided (Just adjust or omit below two strings for next version they code :) @unixfreaxjp), it appears this rule is designed to detect specific text patterns in file contents, commit messages, or log entries that match a conversational or review-style string (likely containing emojis like :), mentions like @unixfreaxjp, and phrases about “next version”).

Here are 4 specific false positive scenarios in an enterprise environment where legitimate activities would trigger this rule:

Original source: https://github.com/Yara-Rules/rules/blob/main/malware/MALW_Rebirth_Vulcan_ELF.yar