Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fb73e6ab2673d94…

MALICIOUS

PDF

82.8 KB Created: 2021-09-03 10:47:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: e3e2f2d3e88e62f64f549a29d6560b74 SHA-1: 4c6b104cdcf8f0393f554a959aee0ee2b8b0dca2 SHA-256: 4fb73e6ab2673d94f1cd6f5c3513f3accc7d8fa44afadf565c100771497ac3bf
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external resources, many of which are hosted on compromised websites and point to other PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. The presence of link farms on disposable or compromised hosting suggests an attempt to obscure the ultimate destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://fujiya-burbank.com/uploads/files/detegogagobole.pdf In PDF document text
    • http://ithalattagarantibelgesi.com/resimlerfiles/kuxorajetexokogoguvaxoj.pdfIn PDF document text
    • https://seikai.jp/free_images/files/88643197227.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/66db9b421e13a4aa0965b45bcfad2cb6/lofedowasexuveguduzewe.pdfIn PDF document text
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/3c288b9976be3b7fd667893486b38a4f/3337070022.pdfIn PDF document text
    • http://www.cenlaenvironmental.com/siteuploads/editorimg/file/57102982877.pdfIn PDF document text
    • https://giolog.biz/images/bulk_images/files/borigajozos.pdfIn PDF document text
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099ef995599f---tokugaxasorolowawoki.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/bcus3rftf3katfdkhb88geh5it/79450192049.pdfIn PDF document text
    • http://matstravel.ru/userfiles/file/39716972194.pdfIn PDF document text
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/gujebapejapogez.pdfIn PDF document text
    • http://zoo-foto.cz/userfiles/file/98064381824.pdfIn PDF document text
    • http://andrelandberg.com/userfiles/file/48084187608.pdfIn PDF document text
    • http://kkitv.com/images/upload/File/94932361746.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/ohcnsq47njc8i0ts1ape9r8svt/18055273518.pdfIn PDF document text
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160894db90f330---3665167877.pdfIn PDF document text
    • http://snsi.jp/image/news_file/bapelizegij.pdfIn PDF document text
    • http://wib24-admin.de/uploads/file/tamumi.pdfIn PDF document text
    • https://dutchfansitenetwork.nl/ckfinder/userfiles/files/dowegijoxopageravubo.pdfIn PDF document text
    • http://forglory.cz/ckfinder/userfiles/files/78390026840.pdfIn PDF document text
    • http://aaaexpressheating.com/userfiles/file/makanif.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079a340479b7---wasinelawe.pdfIn PDF document text
    • https://www.groupenahno.com/wp-content/plugins/super-forms/uploads/php/files/v4gud73c16r705tsd33t5i2s9j/11665303825.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612e59d62e045---6598695207.pdfIn PDF document text
    • http://leebyunghun.kr/new/upload/board/files/56772340881.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=business+introduction+letter+format+pdfPDF 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_off0000df9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF9A 17344 bytes
SHA-256: 914c4cf5284d3f11d757e4d22a7f091848768c88896a2decdbf6b4bb8a2f500a
font_01_sfnt_off00010c5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C5E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012475.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12475 10936 bytes
SHA-256: b60148d9dda7ebe7662abdcde9f95e495b5eaa71535e487e89b4be3e0da46d1e