Malicious PDF — malware analysis report

Static analysis result for SHA-256 d7813fb1353b38fe…

MALICIOUS

PDF

82.9 KB Created: 2021-09-10 22:54:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 691cefe162e5887ce01861d83de6f83e SHA-1: 9938e44b52438f82481a19ddafcc0a9f7cb1d10c SHA-256: d7813fb1353b38fe0ff9993fd6a57b148e59bb9481fd1285c49dae1ba2a69139
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links, many of which are part of a link farm designed to redirect users to various hosting sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the presence of multiple unknown-reputation URLs suggest a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or trojan delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://huntic.ru/uplcv?utm_term=idm+download+2021 PDF link annotation
    • http://cserepakcio.hu/xdata/file/niwatelunipe.pdfIn PDF document text
    • http://mishelik.ru/userfiles/file/nilivuvenupovusevonev.pdfIn PDF document text
    • https://etest.vn/app/webroot/uploads/files/14783859704.pdfIn PDF document text
    • https://rrr71.ru/upload_picture/monojafe.pdfIn PDF document text
    • https://vico-domrep.com/ckfinder/userfiles/files/93225015143.pdfIn PDF document text
    • http://acsalma.hu/userfiles/files/xujinupo.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/161325ac4d9ce0---74527681003.pdfIn PDF document text
    • https://wrd13.com/force/file/615139733.pdfIn PDF document text
    • http://apisicul.com/userfiles/files/50249260308.pdfIn PDF document text
    • http://ozkayalarlojistik.com/userfiles/file/15094635596.pdfIn PDF document text
    • http://lube-stc.com/ckfinder/userfiles/files/vanebesaveta.pdfIn PDF document text
    • https://lanna-flyingclub.com/ckfinder/userfiles/files/vatelimuju.pdfIn PDF document text
    • http://apartmany.cucoriedka.sk/data/files/melitajajisil.pdfIn PDF document text
    • http://kalmi.ru/upfiles/files/ribemowurigegez.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/58680c99bf4c8c72f790ea08d2b7c976/buzevamilebujajobolupaxo.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16138ee70e9350---89363509072.pdfIn PDF document text
    • http://moderncarrent.com/user_img/files/19916868079.pdfIn PDF document text
    • https://cvsc.co/userfiles/file/8655416941.pdfIn PDF document text
    • https://hosvagyok.hu/userfiles/file/boretoruwopujere.pdfIn PDF document text
    • http://chhattisgarhsanskritboard.in/sharpinstitute/images/files/1626965402.pdfIn PDF document text
    • http://olimpic.hu/ckfinder/userfiles/files/4984758228.pdfIn PDF document text
    • https://pernambucoimortal.com/imagens/files/705152878.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/tetij.pdfIn PDF document text
    • http://ormansagszive.hu/upload/file/74757612882.pdfIn PDF document text
    • http://carsonpokebar.com/uploads/files/85767969356.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_off0000e18e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE18E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f9a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A0 17704 bytes
SHA-256: 5d276980afd6fd81f08744b5a436f5a8a01720c6250b76e248c9072d88ef63ba
font_02_sfnt_off00012771.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12771 10148 bytes
SHA-256: cfe12a5d6abdb7bb472cbeb81924fa391ffddd4f4949aaf4625489254ad061f7