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YARA · Volexity threat-intel

VOLEXITY_Hacktool_Golang_Reversessh_Fahrj

Detects a reverse SSH utility available on GitHub. Attackers may use this tool or similar tools in post-exploitation activity.

Hack toolVolexity threat-intelBSD 2-Clause LicenseCompiles with YARA-X (with warnings)
Author
threatintel@volexity.com
Date
2024-04-10
Modified
2024-04-12
Score / Quality
75 / 80

What this rule detects

Detects a reverse SSH utility available on GitHub. Attackers may use this tool or similar tools in post-exploitation activity.

It defines 10 patterns (10 text, 0 hex, 0 regex).

YARA-X says: warning[duplicate_pattern_value]: duplicate pattern value

Summary generated from the rule's metadata and condition.

Rule source

hacktool-golang-reversessh-fahrj.yarBSD 2-Clause License
rule VOLEXITY_Hacktool_Golang_Reversessh_Fahrj : FILE MEMORY
{
	meta:
		description = "Detects a reverse SSH utility available on GitHub. Attackers may use this tool or similar tools in post-exploitation activity."
		author = "threatintel@volexity.com"
		id = "332e323f-cb16-5aa2-8b66-f3d6d50d94f2"
		date = "2024-04-10"
		modified = "2024-04-12"
		reference = "TIB-20240412"
		source_url = "https://github.com/volexity/threat-intel/blob/3a9d0b52459877ee866a9a0ba06e60059b778c77/2024/2024-04-12 Palo Alto Networks GlobalProtect/indicators/rules.yar#L82-L116"
		license_url = "https://github.com/volexity/threat-intel/blob/3a9d0b52459877ee866a9a0ba06e60059b778c77/LICENSE.txt"
		hash = "161fd76c83e557269bee39a57baa2ccbbac679f59d9adff1e1b73b0f4bb277a6"
		logic_hash = "38b40cc7fc1e601da2c7a825f1c2eff209093875a5829ddd2f4c5ad438d660f8"
		score = 75
		quality = 80
		tags = "FILE, MEMORY"
		os = "all"
		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 = 10423
		version = 5

	strings:
		$fun_1 = "createLocalPortForwardingCallback"
		$fun_2 = "createReversePortForwardingCallback"
		$fun_3 = "createPasswordHandler"
		$fun_4 = "createPublicKeyHandler"
		$fun_5 = "createSFTPHandler"
		$fun_6 = "dialHomeAndListen"
		$fun_7 = "createExtraInfoHandler"
		$fun_8 = "createSSHSessionHandler"
		$fun_9 = "createReversePortForwardingCallback"
		$proj_1 = "github.com/Fahrj/reverse-ssh"

	condition:
		any of ( $proj_* ) or 4 of ( $fun_* )
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$fun_1text"createLocalPortForwardingCallback"
$fun_2text"createReversePortForwardingCallback"
$fun_3text"createPasswordHandler"
$fun_4text"createPublicKeyHandler"
$fun_5text"createSFTPHandler"
$fun_6text"dialHomeAndListen"
$fun_7text"createExtraInfoHandler"
$fun_8text"createSSHSessionHandler"
$fun_9text"createReversePortForwardingCallback"
$proj_1text"github.com/Fahrj/reverse-ssh"

Condition

any of ( $proj_* ) or 4 of ( $fun_* )

In plain words (Heuristic)

  • At least one pattern in ( $proj_* ) must match.
  • At least 4 patterns in ( $fun_* ) must match.

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Sample hashes

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

  • 161fd76c83e557269bee39a57baa2ccbbac679f59d9adff1e1b73b0f4bb277a6

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: 332e323f-cb16-5aa2-8b66-f3d6d50d94f2

Metadata

osall
os_archall
scan_contextfile,memory
severitycritical
rule_id10423
version5

Tags:FILEMEMORY