Malicious PDF — malware analysis report

Static analysis result for SHA-256 4db76a666a43491b…

MALICIOUS

PDF

95.0 KB Created: 2021-09-10 11:10:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8d74254b910da2545d0b4617bcb0bd68 SHA-1: ae75479ebc45392a126ba37f1c72964f064bf342 SHA-256: 4db76a666a43491b2e8fd718119490d365b6f500bfddf1391aa7a8a9a63ce376
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to distribute malicious content. ClamAV detected this file as 'Pdf.Phishing.Trojan', and ML classification strongly supports its malicious nature. The primary attack pattern observed is the use of a malicious document as an attachment in spearphishing campaigns to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://timnhanhonline.com/upload/files/38290917066.pdf In PDF document text
    • http://espwireless.net/uploads/file/53289664486.pdfIn PDF document text
    • http://czytamzezrozumieniem.pl/userfiles/file/kaburubaxokutola.pdfIn PDF document text
    • http://beta-rc.com/upload/files/3769326585.pdfIn PDF document text
    • https://iwanbim.iwan.co/userfiles/files/xulatokib.pdfIn PDF document text
    • http://popnmusic.fr/userfiles/file/42773924286.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135652220f03---ronomutuloxukinutim.pdfIn PDF document text
    • http://loca-granderoue-montaletang.com/ckfinder/userfiles/files/2991744466.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-8/20210908002216159697.pdfIn PDF document text
    • https://tonmathunglan.vn/upload/files/96583539164.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612eca7a10b5c---93968783857.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec8dfbdb91---53617014035.pdfIn PDF document text
    • http://cpgny.com/userfiles/files/nakiwipanerifabika.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/8bdcac2cc7763a6b8b511bcf8608c067/gogezixab.pdfIn PDF document text
    • http://motorlustor.net/userfiles/file/6295401571.pdfIn PDF document text
    • https://mcrlclient.gilcom.ro/ckfinder/userfiles/files/90688463173.pdfIn PDF document text
    • http://steakclubhn.com/campannas/file/3243419206.pdfIn PDF document text
    • https://vili-al.com/uploads/wysiwyg/files/27369959128.pdfIn PDF document text
    • http://giayviettri.com/img-ftec/files/37848872455.pdfIn PDF document text
    • https://bamfieldrental.com/userfiles/file/repuvazesewuxa.pdfIn PDF document text
    • http://jmyhship.com/uploadfile/files/vulabukej.pdfIn PDF document text
    • https://jmbarrenetxea.soinuenea.eus/files/galeria/files/4565767735.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=all+star+game+watch+online+freePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010ae3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AE3 19316 bytes
SHA-256: 79fbd221e78d501d6fe4e65de1a4c91a6cd277beee1a0dd02201e34d142675ec
font_01_sfnt_off00013d3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D3A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015551.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15551 10852 bytes
SHA-256: f223e50e8d742385cc00205986c6132184477b053f5847b8e6fdcfe1a8a32a08