Malicious PDF — malware analysis report

Static analysis result for SHA-256 7d21015764abf81a…

MALICIOUS

PDF

73.7 KB Created: 2021-08-28 22:58:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: be63250500d76c27fc45a6c783e6f985 SHA-1: 94c8be0f9bc339e401cef68e3119a864a290148c SHA-256: 7d21015764abf81af3ea63c3734713483871e3e3ff1298aa08af19900f9c2593
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://bellina.pl/userfiles/file/kotobudevu.pdf In PDF document text
    • http://aaz.sk/editor_uploads/files/74248635520.pdfIn PDF document text
    • http://watch62.ru/files/files/29013685564.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/4149cd7927119e06224193acaec4a37a/34248144143.pdfIn PDF document text
    • http://waltwhitmanclassof1965.com/clients/c/cc/ccbfa8a87e297cd67510599b8aebcb74/File/jowexofurud.pdfIn PDF document text
    • http://ingfrimale.com/userfiles/files/34055532686.pdfIn PDF document text
    • http://veterina-hrib.cz/user-uploads/files/70306323131.pdfIn PDF document text
    • https://5udua.com/contents//files/difaku.pdfIn PDF document text
    • http://gocep.org/data/userfiles/files/16869050449.pdfIn PDF document text
    • http://maslag.eu/userfiles/file/zawikusoxafunok.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16092af05d8068---kevowupuxiki.pdfIn PDF document text
    • http://bfo-walkforhope.com/clients/e/eb/ebd0efab9cd97e953e90891d9eec7aad/File/19435545279.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16081935ae9401---68174565858.pdfIn PDF document text
    • http://izumrud38.com/ckfinder/userfiles/files/59567706796.pdfIn PDF document text
    • https://strategieb2b.com/userfiles/file/vuden.pdfIn PDF document text
    • http://makesomenoise.hu/upload/file/wavolekeli.pdfIn PDF document text
    • http://sendedianqi.com/upload_fck/file/2021-7-4/20210704084421259308.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/d1bpjje1hkkgefrrahvcnj2244/jikajagosojugakusonamej.pdfIn PDF document text
    • http://getampedmag.com/ckfinder/userfiles/files/15865709253.pdfIn PDF document text
    • http://icmasistemas.com/userfiles/files/vazisuwilorosiwebinowufo.pdfIn PDF document text
    • https://motelandratecuci.ro/userfiles/file/85239729397.pdfIn PDF document text
    • http://tongkhomica.com/upload/files/vuwopisixatefufebufolizi.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/filavimavakufuzolodiz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=batch+read+file+into+variablePDF 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_off0000bbda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBDA 16940 bytes
SHA-256: 3dd0a3629b611572ae96974d840cd9e7d81fc31853c733b1f266709cf9502267
font_01_sfnt_off0000e854.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE854 10664 bytes
SHA-256: e52c9f2cccd78150bb4fc5e6766018e9176a00c85b056a1308666af4da86ae1f
font_02_sfnt_off000100b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100B9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1