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VOLEXITY_Webshell_Jsp_Regeorg

Detects the reGeorg webshells' JSP version.

WebshellVolexity threat-intelBSD 2-Clause LicenseCompiles with YARA-X
Author
threatintel@volexity.com
Date
2022-03-08
Modified
2024-09-20
Score / Quality
75 / 80

What this rule detects

Detects the reGeorg webshells' JSP version.

It defines 6 patterns (6 text, 0 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

webshell-jsp-regeorg.yarBSD 2-Clause License
rule VOLEXITY_Webshell_Jsp_Regeorg : FILE MEMORY
{
	meta:
		description = "Detects the reGeorg webshells' JSP version."
		author = "threatintel@volexity.com"
		id = "205ee383-4298-5469-a509-4ce3eaf9dd0e"
		date = "2022-03-08"
		modified = "2024-09-20"
		reference = "https://github.com/SecWiki/WebShell-2/blob/master/reGeorg-master/tunnel.jsp"
		source_url = "https://github.com/volexity/threat-intel/blob/3a9d0b52459877ee866a9a0ba06e60059b778c77/2022/2022-08-10 Mass exploitation of (Un)authenticated Zimbra RCE CVE-2022-27925/yara.yar#L57-L86"
		license_url = "https://github.com/volexity/threat-intel/blob/3a9d0b52459877ee866a9a0ba06e60059b778c77/LICENSE.txt"
		hash = "f9b20324f4239a8c82042d8207e35776d6777b6305974964cd9ccc09d431b845"
		logic_hash = "cecb71605d9112d509823c26e40e1cf9cd6db581db448db5c9ffc63a2bfe529e"
		score = 75
		quality = 80
		tags = "FILE, MEMORY"
		os = "win"
		os_arch = "all"
		scan_context = "file,memory"
		severity = "critical"
		license = "See license at https://github.com/volexity/threat-intel/blob/main/LICENSE.txt"
		rule_id = 6575
		version = 5

	strings:
		$magic = "socketChannel.connect(new InetSocketAddress(target, port))" ascii
		$a1 = ".connect(new InetSocketAddress" ascii
		$a2 = ".configureBlocking(false)" ascii
		$a3 = ".setHeader(" ascii
		$a4 = ".getHeader(" ascii
		$a5 = ".flip();" ascii

	condition:
		$magic or all of ( $a* )
}

Strings (6 patterns)

IdentifierTypeValueModifiers
$magictext"socketChannel.connect(new InetSocketAddress(target, port))"ascii
$a1text".connect(new InetSocketAddress"ascii
$a2text".configureBlocking(false)"ascii
$a3text".setHeader("ascii
$a4text".getHeader("ascii
$a5text".flip();"ascii

Condition

$magic or all of ( $a* )

In plain words (Heuristic)

  • All patterns in ( $a* ) must match.
  • Pattern $magic must be present.

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References

Sample hashes

Hashes of samples the author lists in the rule's meta (look them up in your threat-intelligence platform).

  • f9b20324f4239a8c82042d8207e35776d6777b6305974964cd9ccc09d431b845

Licence & attribution

Author: threatintel@volexity.com

Source repository: Volexity threat-intel @ 3a9d0b5245

Licence: BSD 2-Clause License (stated in the rule's own meta)

“See license at https://github.com/volexity/threat-intel/blob/main/LICENSE.txt”

Copyright notice: Copyright 2022 by Volexity, Inc.

Original rule

Mirrored via YARA Forge 20260927, which prefixes rule names with the source and adds normalised meta fields.

Rule id: 205ee383-4298-5469-a509-4ce3eaf9dd0e

Metadata

oswin
os_archall
scan_contextfile,memory
severitycritical
rule_id6575
version5

Tags:FILEMEMORY