Malicious PDF — malware analysis report

Static analysis result for SHA-256 781f0c15c98606c6…

MALICIOUS

PDF

71.0 KB Created: 2021-09-17 18:26:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d0beb969b9df5c2c751561f664d6b080 SHA-1: aeb62f908535b86823141a4d2c330817e6e28245 SHA-256: 781f0c15c98606c650006d84f422e72d2907d5c105ae6dd53d496a0fd6866a3d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to websites hosted on compromised CMS platforms or disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery mechanisms.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://nomylo.ru/uplcv?utm_term=samsung+frp+unlocker PDF link annotation
    • https://karolinanowak.com/userfiles/file/xobezegovinobawuxi.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/16132f010eba96---wadosotimopurunokosik.pdfIn PDF document text
    • http://tdsns.ru/userfiles/file/98988810069.pdfIn PDF document text
    • http://mcap.cz/images/uploadedimages/file/98768400972.pdfIn PDF document text
    • http://vmkmsz.hu/userfiles/file/52382132024.pdfIn PDF document text
    • http://velapower.com/glwh/UploadFile/file/2021090312160873499.pdfIn PDF document text
    • https://digireg.it/upload/donuba.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/0h8n2rh3jmsnlmgrj9223sat7e/butabanikenu.pdfIn PDF document text
    • https://sunsoftinfoway.net/ckfinder/userfiles/files/72376054265.pdfIn PDF document text
    • http://njchemland.com/upload/files/jukobivoganujakisuzawotub.pdfIn PDF document text
    • https://thepainter.asia/upload/files/mazamukolano.pdfIn PDF document text
    • http://fqcycpa.com/jingkelun/userfiles/files/20210906210019.pdfIn PDF document text
    • http://milwaukee.center/userfiles/file/97928799974.pdfIn PDF document text
    • http://havefuntogether.com/image/upload/File/16723144083.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/25068047130.pdfIn PDF document text
    • https://subded.org/userfiles/file/zafokijadikexe.pdfIn PDF document text
    • http://khunghinhdepphuctin.com/media/ftp/file/pejegopinol.pdfIn PDF document text
    • http://ccsctda.com/ckfinder/userfiles/files/20210901_073109.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/kisunibutobogenuzonaz.pdfIn PDF document text
    • https://semangkabiji.com/contents/files/wejanafosivuvibaxonevi.pdfIn PDF document text
    • http://sun-eko.eu/files/file/33989329868.pdfIn PDF document text
    • https://stauber.lt/images/files/dedufelenofabut.pdfIn PDF document text
    • http://reopen911.info/media/file/vavasexuxuja.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1612efdb4db201---vixeka.pdfIn PDF document text
    • https://my-natural-style.net/upload/files/80311874952.pdfIn PDF document text
    • http://rent-lease-no1.com/userfiles/file/20210915151720.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_off0000b4a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4A9 10900 bytes
SHA-256: 2d8801c688c2594db7ab8fc4df30ff633870d4f6a908c25fd7a5de847330bb7c
font_01_sfnt_off0000cddb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDDB 15900 bytes
SHA-256: 90723208b0862f62ad42a5ae8b7ecb129a2a9611cb2b095a7487ae4066190261
font_02_sfnt_off0000f5fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1