{
	"id": "bdfefda1-ba5a-494f-9206-2c0566ee9229",
	"created_at": "2026-04-06T00:07:51.968271Z",
	"updated_at": "2026-04-10T03:21:48.528098Z",
	"deleted_at": null,
	"sha1_hash": "73513fe38eaa3d0f1de333fe46f20bc24498aee8",
	"title": "TrickBot malware uses obfuscated Windows batch script to evade detection",
	"llm_title": "",
	"authors": "",
	"file_creation_date": "0001-01-01T00:00:00Z",
	"file_modification_date": "0001-01-01T00:00:00Z",
	"file_size": 1777471,
	"plain_text": "TrickBot malware uses obfuscated Windows batch script to evade\r\ndetection\r\nBy Ax Sharma\r\nPublished: 2020-11-24 · Archived: 2026-04-05 14:37:38 UTC\r\nWith the 100th release of TrickBot, the malware came equipped with new and advanced evasive capabilities. One such\r\ncapability is its use of an obfuscated batch script launcher to jumpstart malicious executables.\r\nThe fact that batch scripts need no interpreter but Microsoft Windows' inbuilt command prompt makes this evasion\r\ntechnique self-contained and minimalistic.\r\nTrickBot deploys ransomware via obfuscated BAT scripts\r\nOver the weekend, BleepingComputer's Lawrence Abrams analyzed the hundredth build of TrickBot and its new features.\r\nhttps://www.bleepingcomputer.com/news/security/trickbot-malware-uses-obfuscated-windows-batch-script-to-evade-detection/\r\nPage 1 of 6\n\n0:00\r\nhttps://www.bleepingcomputer.com/news/security/trickbot-malware-uses-obfuscated-windows-batch-script-to-evade-detection/\r\nPage 2 of 6\n\nVisit Advertiser websiteGO TO PAGE\r\nTrickBot is a malware infection commonly installed via malicious phishing emails or other malware. When installed,\r\nTrickBot will quietly run on a victim's computer while it downloads other modules to perform different tasks.\r\nTrickBot is known to finish an attack by giving access to threat actors who deploy either the Ryuk or Conti ransomware on\r\nthe compromised network.\r\nIn our analysis, BleepingComputer had observed a BAT script launcher.bat being run by a scheduled task set up by\r\nTrickBot.\r\nScheduled task that runs launcher.bat\r\nSource: BleepingComputer\r\nBoth the launcher.bat and the executable it launches are present in the same directory, as observed by\r\nBleepingComputer, whose location looks like:\r\nC:\\Users\\(username)\\AppData\\Roaming\\IdentitiesXXXXXXXXXX\\\r\nYet, the use of an obfuscated batch script, shown below, to launch the executable is likely another feature to fly under the\r\nradar of enterprise security products.\r\nhttps://www.bleepingcomputer.com/news/security/trickbot-malware-uses-obfuscated-windows-batch-script-to-evade-detection/\r\nPage 3 of 6\n\nThe obfuscated batch script launcher.bat  further runs the EXE payload\r\nSource: BleepingComputer\r\nRecently, researchers at Huntress Labs discovered another TrickBot sample that used a similar batch script with over 40\r\nlines of obfuscated code.\r\nWhen deciphered, all the code did was launch the malware, an action that could have been triggered by just a single line of\r\ncode:\r\nstart C:\\Users\\██████████\\AppData\\Roaming\\Identities1603031315\\ulib8b4.exe\r\nThe binary in question, \"ulib8b4.exe\" is TrickBot's payload that performs a wide range of malicious activity,\r\nincluding stealing a domain's Active Directory Services database, spreading laterally on a network, screenlocking, stealing\r\ncookies and browser passwords, and stealing OpenSSH keys.\r\n\"System administrators often make use of batch scripting to make their lives easier and speed up their workflow,\" says John\r\nHammond, Senior Security Researcher at Huntress Labs.\r\n\"But since this offers great access to the computer system, threat actors and malware families take advantage of .bat files\r\njust as well.\"\r\nHammond notes although antivirus products could easily scan plain-text batch scripts, the fact an attacker has gone through\r\nmultiple steps to obfuscate a simple one-line command would make it virtually impossible for an \"off-the-shelf\" EDR\r\nor signature-based antivirus product to detect such samples.\r\nFurther, the signature detection can be avoided given there are various ways an attacker could obfuscate the same payload,\r\neach producing a different signature.\r\n\"On the surface, this code is completely unintelligible. It looks like random letters, in a random order, with random percent-signs thrown all around. But cmd.exe will interpret it and execute it, and that old-school shell is the tried and true built-in\r\nthat hackers know will be on a target system,\" said Hammond.\r\nWhy are obfuscated batch scripts uniquely a problem?\r\nhttps://www.bleepingcomputer.com/news/security/trickbot-malware-uses-obfuscated-windows-batch-script-to-evade-detection/\r\nPage 4 of 6\n\nBleepingComputer asked Hammond, considering obfuscation techniques are not limited to batch scripts why was the use of\r\nBAT files in malware uniquely a problem.\r\nIn other words, NodeJS files and Python scripts that contain plain text code, rather than binary data, could be just as well\r\nobfuscated.\r\nHammond told BleepingComputer, \"You're absolutely right—it could very well have been any file or any different language\r\nof code. I think the most interesting gimmick with the BAT/cmd.exe script is that it is native and inherent to a Windows\r\noperating system, so it doesn't need any external compiler or some other means to get the code to execute on the target.\"\r\nFurthermore, the researcher told us, since all of the characters in the batch script were ASCII printable characters, rather than\r\nbinary code, it was easier to transmit the script over the wire while bypassing the scrutiny of antivirus programs.\r\n\"We talk a lot about 'live-off-the-land binaries' and this is a peculiar one because it is not so much a 'binary,' but a trick to\r\nsort of weaponizing one.\"\r\n\"And of course, with all the characters being ASCII printable characters, this snippet can be easily sent over the wire, and\r\nsince there aren't any glaring 'bad strings' or malicious signatures, an EDR or AV program could overlook it,\" the researcher\r\ntold BleepingComputer.\r\nHuntress Labs' detailed insights on the obfuscation technique can be found in their report.\r\nAn improved version of this obfuscation technique has also been demonstrated by Hammond on YouTube.\r\nAutomated Pentesting Covers Only 1 of 6 Surfaces.\r\nAutomated pentesting proves the path exists. BAS proves whether your controls stop it. Most teams run one without the\r\nother.\r\nThis whitepaper maps six validation surfaces, shows where coverage ends, and provides practitioners with three diagnostic\r\nquestions for any tool evaluation.\r\nhttps://www.bleepingcomputer.com/news/security/trickbot-malware-uses-obfuscated-windows-batch-script-to-evade-detection/\r\nPage 5 of 6\n\nSource: https://www.bleepingcomputer.com/news/security/trickbot-malware-uses-obfuscated-windows-batch-script-to-evade-detection/\r\nhttps://www.bleepingcomputer.com/news/security/trickbot-malware-uses-obfuscated-windows-batch-script-to-evade-detection/\r\nPage 6 of 6",
	"extraction_quality": 1,
	"language": "EN",
	"sources": [
		"ETDA"
	],
	"references": [
		"https://www.bleepingcomputer.com/news/security/trickbot-malware-uses-obfuscated-windows-batch-script-to-evade-detection/"
	],
	"report_names": [
		"trickbot-malware-uses-obfuscated-windows-batch-script-to-evade-detection"
	],
	"threat_actors": [],
	"ts_created_at": 1775434071,
	"ts_updated_at": 1775791308,
	"ts_creation_date": 0,
	"ts_modification_date": 0,
	"files": {
		"pdf": "https://archive.orkl.eu/73513fe38eaa3d0f1de333fe46f20bc24498aee8.pdf",
		"text": "https://archive.orkl.eu/73513fe38eaa3d0f1de333fe46f20bc24498aee8.txt",
		"img": "https://archive.orkl.eu/73513fe38eaa3d0f1de333fe46f20bc24498aee8.jpg"
	}
}