Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3c56d7f682926e4…

MALICIOUS

PDF

68.2 KB Created: 2021-09-25 14:17:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: d850cbd43b8e4eb1603d9a044ce2b2ff SHA-1: 0c72e2fa736324e7fab3795229fcb7c2416fbc3a SHA-256: a3c56d7f682926e47303080b2f3a503ca4050737d9b7682dbf1158cf37daabd3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Numerous heuristics indicate the PDF functions as a link farm, with many embedded URLs pointing to potentially compromised websites or disposable hosting. The presence of external URIs and link farms suggests an attempt to redirect users to malicious sites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://oniceh.ru/uplcv?utm_term=how+to+hack+someones+call+recording PDF link annotation
    • https://buyafranchise.org/files/files/47590857545.pdfIn PDF document text
    • http://borneneskontor-landsforening.dk/userfiles/file/55769242372.pdfIn PDF document text
    • http://tostonet.cl/ckfinder/userfiles/files/faxowapuwuxaxagedovibij.pdfIn PDF document text
    • http://www.donboscovizag.org/images/files/41078724278.pdfIn PDF document text
    • https://praktijk-fix.nl/userfiles/image/file/buralu.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ab0726af97---35049003902.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/d2c955f8e2d1d03ce0daf5c70f5d40e7/juponir.pdfIn PDF document text
    • http://orlickachata.cz/files/files/53526882545.pdfIn PDF document text
    • https://markmont.eu/editor_uploads/system/files/govodabetimavawe.pdfIn PDF document text
    • http://mishor-uvk.com/uploads/files/pesaxosuworofezomejadure.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd9e09e982---fozupenaxagibujemamaxut.pdfIn PDF document text
    • http://gemmacapitalgroup.com/foto/file/93507360868.pdfIn PDF document text
    • http://aggengr.com/uploads/CMS/file/denosulogaxi.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613f4830666a8---vasidatavuranirogus.pdfIn PDF document text
    • http://belly.bpv.su/content/files/files/94033833493.pdfIn PDF document text
    • http://gpp300.fr/userfiles/file/puwalazitoporexizoju.pdfIn PDF document text
    • https://atputasbaze.lv/images/userfiles/files/luxegunurosa.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613f5db2cb69b---mupowavux.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149d65906ca1---90356370184.pdfIn PDF document text
    • https://prolocolidodisavio.org/ckfinder/userfiles/files/xazokukapixizuzudo.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/83828173794.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_off0000acae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xACAE 10984 bytes
SHA-256: 8325d8afa35b86d210162ae5d3bc69a1cb65e7aa75e2773718d7b3967e9daf17
font_01_sfnt_off0000c5cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5CB 14276 bytes
SHA-256: 435ad14f9a246b6e3d9a35397ac96cc6819f66f45ed74a0b42fb660358a8287b
font_02_sfnt_off0000e991.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE991 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1