Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4cafb39794d34dd…

MALICIOUS

PDF

75.4 KB Created: 2021-09-21 20:56:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b3073e708174825593a4a9287ffcada7 SHA-1: 4a19e3a27a8a6bad84d450b7acf8fa31971c20e5 SHA-256: a4cafb39794d34dd93ba4dad69a2d96ca405dd0c171ce7a3bb20520e4871ec25
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with many embedded URLs pointing to various domains, including compromised WordPress upload directories. This suggests the document is designed to lure users to potentially malicious sites, possibly for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://z500.si/files/nirovopumuwoxalijuxupofos.pdf In PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/161443aeeb1394---80988529079.pdfIn PDF document text
    • https://7mark3t2-7aya.com/contents/files/ginatunopakonapop.pdfIn PDF document text
    • http://geteffective.biz/uploadfiles/file/81208202503.pdfIn PDF document text
    • http://togul.org/sites/default/files/file/dapoxekus.pdfIn PDF document text
    • https://kueapem.com/contents/files/30742924629.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612efa11910b9---kabijurevefaximuk.pdfIn PDF document text
    • https://marblo.com/app/webroot/img/files/midezumariwawoxumakamaka.pdfIn PDF document text
    • http://qdjshg.com/files/file/42242637798.pdfIn PDF document text
    • http://yokosohk.com/files/fckfiles/file/65836806675.pdfIn PDF document text
    • https://hopadive.cz/ckfinder/userfiles/files/70948512156.pdfIn PDF document text
    • http://exhibitionchannel.com/upload/35236434092.pdfIn PDF document text
    • https://penmypoem.com/new/admin/uploadfiles/file/gupazigido.pdfIn PDF document text
    • http://nanopena.cz/upload/file/29445308181.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/to1ij58lis1a4c4u2a20ucki0u/55493106646.pdfIn PDF document text
    • http://clubselectionvoyages.net/images/file/10572661995.pdfIn PDF document text
    • https://nsstore.mx/ckeditor/ckfinder/archivossubidos/files/2031377180.pdfIn PDF document text
    • http://anhuizpyy.com/upload_fck/file/2021-9-9/20210909170246545441.pdfIn PDF document text
    • https://newegys.egyseg.eu/ckfinder/userfiles/files/kesuxiriforawowutubokiguk.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/e3d6d68f37227fe60cd52d8191757f7d/monebupopimogasulezev.pdfIn PDF document text
    • http://leprofit.ee/cmsfile/contentfiles/nodadopi.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/f6sj2f7inht7ohtakhl2gnfqq7/87686998103.pdfIn PDF document text
    • https://medosojewellery.com/userfiles/files/36095022700.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+delete+my+purchase+history+in+play+storePDF link annotation
    • http://zs.tom.ru/jsplugins/ckfinder/userfiles/files/72019801249.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_off0000c18a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC18A 17136 bytes
SHA-256: 3b0abe19643e683a4d33d1e1305c6c749846638a84d2639724d64fa5876c7245
font_01_sfnt_off0000ee2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE2D 11072 bytes
SHA-256: bb1703be1452eafcf78710b624eb8ebe98fbce7c6c653fea07f881bfcf6071b3
font_02_sfnt_off000107d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1