Malicious PDF — malware analysis report

Static analysis result for SHA-256 677bbaf1063e33df…

MALICIOUS

PDF

72.7 KB Created: 2021-09-17 19:33:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 0ef1bdd77b871fef3978090e46722928 SHA-1: 7abdff6b56199bc2d58e211377fb5e0e8dccc08a SHA-256: 677bbaf1063e33dfa049fe3d3a677df5b24210881bed8e5e8ef7978272936dff
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 https://crewmak.ru/uplcv?utm_term=the+fancy+pants+3 PDF link annotation
    • http://thuocamakong.net/userfiles/image/file/karefizamoxalexeroz.pdfIn PDF document text
    • http://tandartsindex.nl/images/uploads/wavipumatixomi.pdfIn PDF document text
    • https://saint-florentin.charcutier-traiteur.fr/ckfinder/userfiles/files/25193918575.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/33be96e0834489c7f262ceb14aa4f064/92810226395.pdfIn PDF document text
    • http://metalzilemboeventi.com/userfiles/files/nujoruguwejaguluxunasijav.pdfIn PDF document text
    • http://kientrucphatloc.com/upload/files/41990977560.pdfIn PDF document text
    • http://express-service-auto.fr/ckeditor/ckfinder/userfiles/files/2505791909.pdfIn PDF document text
    • https://saatyapi.com/upload/ckfinder/files/32956268983.pdfIn PDF document text
    • http://laxycoffee.com/upload/files/85536919119.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/716da5c89ec2e1cdb4f63ab548c281de/96380258460.pdfIn PDF document text
    • https://medsplus.us/admin/images/file/34878387372.pdfIn PDF document text
    • http://abwingstop.com/uploads/files/19302640007.pdfIn PDF document text
    • http://4seasonstours.in/userfiles/file/fenipeboxasadexufijixewu.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/16143765da13ab---33764683250.pdfIn PDF document text
    • http://www.medicellbank.com/userfiles/files/sexorevibapulilodekizes.pdfIn PDF document text
    • http://hoangnampte.vn/quangbasanpham/app/webroot/upload/image/files/gofidirag.pdfIn PDF document text
    • http://srcchaika.ru/files/uploads/files/169469145.pdfIn PDF document text
    • http://myshopgroup.com/userfiles/files/neremozofokikadozotagurel.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132e80ed58b6---92723863318.pdfIn PDF document text
    • http://acecaalcoy.com/userfiles/file/70817988455.pdfIn PDF document text
    • https://kristinanamaste.eu/files/23391873296.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/16142524dec9bd---foduzedezesawuna.pdfIn PDF document text
    • 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_off0000bc78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC78 16208 bytes
SHA-256: aaeb1e6249895e9c06a4a8b5861a301e57809921753ca821cbd39862f5ad6109
font_01_sfnt_off0000e58f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE58F 10468 bytes
SHA-256: d7c1a6920204dcc6e7dd64815134756e30ec5dd4e394e77612867671d0cb8e82
font_02_sfnt_off0000fd64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD64 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1