Malicious PDF — malware analysis report

Static analysis result for SHA-256 16503066070d951b…

MALICIOUS

PDF

90.7 KB Created: 2021-08-03 14:24:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 52802e3f1502e5978163232c1578ad48 SHA-1: fa0073eb89649a9f99552e8f4a1c11bb9a983c09 SHA-256: 16503066070d951b191171e80550b41acb74b0f936e81f2a8801a7c31535f667
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF containing numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, indicating a link farm for phishing or malware distribution. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were directly extracted, the PDF structure and embedded URLs are indicative of a phishing or credential harvesting attempt, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9932

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://smidgel.ru/uplcv?utm_term=qual+a+raiz+quadrada+de+3136 PDF link annotation
    • http://koopmankennedyfeller.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/rodakuri.pdfIn PDF document text
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160e7047027486---makufevorurunude.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a52d3db4651---vivizagujepidoxegewuweviv.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/160c6f4e919383---7706745224.pdfIn PDF document text
    • http://ohmytour.kr/FileData/ckfinder/files/20210803_67A17E46A51E98D0.pdfIn PDF document text
    • http://ourdesign.hk/ckfinder/userfiles/files/misivutoz.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/71273419377.pdfIn PDF document text
    • http://uelzecht.lu/userfiles/files/38670661205.pdfIn PDF document text
    • http://sunwisechem.com/Uploadfiles/files/9705378137.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/9dd6a2ac291bcbe027c2356f8b2cbacd/27701447283.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c8a28445791---26336819897.pdfIn PDF document text
    • https://hartwellcook.com/wp-content/plugins/super-forms/uploads/php/files/01fcf4be95ec918fc17862312522fe72/41369605863.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/4f1e4ad06b92bb8c515729c73a6df23a/zukopofilig.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160de4bf8e56c8---92837906275.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/ba1a79bf3a8cf33ddb02019c001a3e08/57084187632.pdfIn PDF document text
    • http://www.gesas.it/media/mailinglist/file/7674623559.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/it5n2sd5hscluquvca5nr9v397/13415568947.pdfIn PDF document text
    • https://www.expoagrogto.com/wp-content/plugins/super-forms/uploads/php/files/485usp0ovr6oc13h5ppcbt48u3/jogonaditamenefusa.pdfIn PDF document text
    • http://mistral-paints.cz/userfiles/files/47858609686.pdfIn PDF document text
    • http://shssailors1969.com/clients/3/36/366f78b21138e0f8005dfe6cc5e09e30/File/12170837501.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/pudurojeta.pdfIn PDF document text
    • https://lightsourceindiana.com/wp-content/plugins/super-forms/uploads/php/files/b1752c946293053faf9eb813af33a8b1/56808714141.pdfIn PDF document text
    • http://sanxuatbanthinghiem.org/app/webroot/uploads/files/57211561918.pdfIn PDF document text
    • http://afgventuregroup.com/cfiles/file/xuteragetozexavomotas.pdfIn PDF document text
    • https://ehotelgateway.com/bot/ckfinder/uf/files/7336281253.pdfIn PDF document text
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/g6i7el1ou82l1vhpmi3p1edpes/88570841047.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_off0000fb8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB8D 10508 bytes
SHA-256: 5f2d830ed7eadf2b2ed5f02d2efa7637a8fc36077655e77f9611b56b377cdcb2
font_01_sfnt_off0001137c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1137C 19444 bytes
SHA-256: 76d29ee474b4c6470a4aff6bfaa6e720f80a9589ec397315485d9e21aad3cc48
font_02_sfnt_off00014408.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14408 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1