Malicious PDF — malware analysis report

Static analysis result for SHA-256 834d8d33db90a837…

MALICIOUS

PDF

92.2 KB Created: 2021-07-22 21:51:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 8285cb6b509b7205e939a9b93eb0a99a SHA-1: 066aa05de7e8c25cc0f0ac47d5862a5f432b7983 SHA-256: 834d8d33db90a8371029f6a44bb9c9f5f80d45e3dcb36e1a7f044a515e494ee4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains a link farm pointing to numerous PDF files hosted on compromised CMS uploads, suggesting a phishing or SEO poisoning campaign. While no scripts were directly extracted, the nature of the links and the detection indicate a malicious intent to lure users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9866

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://carroll1975.com/clients/4/4e/4e2b018d07aaa5a30c3e4fca1c7a8df7/File/nawiwixanilisukivovuzo.pdf In PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c174ac47b78---71097626995.pdfIn PDF document text
    • https://funkydrop.shop/wp-content/plugins/super-forms/uploads/php/files/61ac7528621ca547b19963329756a028/84556705156.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/7d7be910bafd6463c4526ab787d10ca1/98970016365.pdfIn PDF document text
    • http://studiotecnicomaglio.it/userfiles/files/80738378243.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ecace12f575---relusumijuno.pdfIn PDF document text
    • https://cnc-ar.ro/files/file/83323100840.pdfIn PDF document text
    • https://autosaloncenter.com/uploads/files/jepomozijak.pdfIn PDF document text
    • http://bahtiyardishekimi.com/fckfiles/file/gimul.pdfIn PDF document text
    • http://bukharageorgia.com/sites/default/files/file/41095226378.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/96950040921.pdfIn PDF document text
    • https://saam.vn/images/content/file/mesajabogu.pdfIn PDF document text
    • https://goldenparadisestsimons.com/wp-content/plugins/super-forms/uploads/php/files/7d414ec4c1d56cd2c15e2cfb22486838/xamina.pdfIn PDF document text
    • http://marty-triple-m.ch/inhalt/files/20879916683.pdfIn PDF document text
    • http://akekaluck.com/ckfinder/userfiles/files/36494468594.pdfIn PDF document text
    • https://honghow.com/ckfinder/userfiles/files/tegesojapobexifer.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/de7e44e311a7ea25efeb5af03fa03788/referadarutiloxesegol.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a71e172a70e---tutixigamanono.pdfIn PDF document text
    • http://www.morrisjones.co.uk/EditorImages/file/14910850479.pdfIn PDF document text
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16088b20841657---55709721503.pdfIn PDF document text
    • http://yevres.fr/ckfinder/userfiles/files/69101796291.pdfIn PDF document text
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c502e9e7cad---belegonijozupulekudu.pdfIn PDF document text
    • http://csc020.com/userfiles/file/20210627062241_04uojm.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a472b0ae4f---73780565147.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dc5dc5064a---lujizodiz.pdfIn PDF document text
    • https://www.carrentchiengmai.com/files/medixitoga.pdfIn PDF document text
    • http://traviet36.com/upload/files/pusuzagapuw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=hiking+trails+lincoln+nhPDF 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_off00010439.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10439 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011c50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C50 10460 bytes
SHA-256: da419f2fa616a1a7df38251cc58d89c695e62dbcda9dfb5f233b01e96b171d04
font_02_sfnt_off000133ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133EC 17480 bytes
SHA-256: 3a02b9bc0c366c89f56d69486ad03eac99a1160158ebeddb2c046156d626f899