Malicious PDF — malware analysis report

Static analysis result for SHA-256 31b9bd74641cc6d7…

MALICIOUS

PDF

74.5 KB Created: 2021-06-30 19:26:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: 3cb1f6214ca9347e033083e1148024a3 SHA-1: ddeb4ccf9dbfd37a8f7ead553ae1eccb65f6789e SHA-256: 31b9bd74641cc6d74a2aeb642aa09bd960aa124eb1a77406c8507e14c375a7f6
154 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 0.8537

Heuristics 5

  • 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
  • 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://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/sankhc4ockhtlfkl8rtk1qbl4h/48213611283.pdf In PDF document text
    • http://bjhtdszdh.com/v15/Upload/file/202162371481004.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074cfd12ce66---53678769024.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a5e84b8ee5---5829424795.pdfIn PDF document text
    • http://sonnenheizungen.ch/fckeditor/editor/images/file/16670209592.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/1609254dd9833b---rabolubexevefaludit.pdfIn PDF document text
    • https://www.dartmusicfestival.co.uk/wp-content/plugins/super-forms/uploads/php/files/af5c899318453be33598e2b9d456a070/pelubuwebozakujep.pdfIn PDF document text
    • http://debsluxe.com/clients/1/17/174397649ed9f07baa8f9d9f48c72a4d/File/43897814843.pdfIn PDF document text
    • http://sushi-belovo.ru/files/26077854711.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160baf5709d2cf---badigeg.pdfIn PDF document text
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/b9eafdec9b427db68bc96ac584c7e9cc/11353544323.pdfIn PDF document text
    • https://realestateconnect.biz/wp-content/plugins/super-forms/uploads/php/files/7cku2b92hhe0sa3a6vdnmte5a6/gamobavuvusututepurufik.pdfIn PDF document text
    • http://hongdanhaudio.com/luutru/files/lisoverumet.pdfIn PDF document text
    • http://fobosgrunt.ru/files/ckfinder/files/tafamanad.pdfIn PDF document text
    • https://securityguardsupply.org/php/uploads/file/vowenalifuvewugomeba.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/1844638241529d72eef040d5317ba7b5/fogolujulil.pdfIn PDF document text
    • https://baongochoa.com/upload/file/fadetej.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608034638a76a---23263230965.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-4-30/20210430000953912886.pdfIn PDF document text
    • http://emilygrilltogo.com/uploads/files/95286626066.pdfIn PDF document text
    • http://thaoduocquyhiem.com/userfiles/image/file/rukubetukorej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=what+if+my+puppy+whines+in+his+cratePDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f613.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF613 10872 bytes
SHA-256: 9c201539a78dece220f27a8c6294e8995c94524634251709c6b84fd6e847fb1f