Malicious PDF — malware analysis report

Static analysis result for SHA-256 a37bf8906c4d0128…

MALICIOUS

PDF

85.2 KB Created: 2021-09-12 06:54:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: d29b4331870e63c6171f1f849b27ab85 SHA-1: 3e01b3d4fec866594808b124c3df05878872eb6c SHA-256: a37bf8906c4d0128331b0db94f0c94d8680e6694834e201decbab1e11a2e465a
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 0.9912

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://arabstina.com/ckfinder/userfiles/files/pefeledowazu.pdf In PDF document text
    • https://www.institutvzdelavani.cz/files/dalofafekot.pdfIn PDF document text
    • https://oncetrabzon.com/resimler/files/xokibagunugigorabuvuzilad.pdfIn PDF document text
    • http://rkmaster.ru/uploads/files/36539667429.pdfIn PDF document text
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/8e6dfe2ead624ccf036d3ae57e1873ff/zitepavopajez.pdfIn PDF document text
    • http://shangrilayunnan.com/ckfinder/userfiles/files/20619204295.pdfIn PDF document text
    • https://vkgnassociates.com/dayafter/uploadimages/newsimages/file/zadamivasovugazepegulopig.pdfIn PDF document text
    • http://ckudzcssffhhj.handysociality.com/upload/files/9225825606.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/e1er49hkoja7gfpsf5jtljb2df/67422649048.pdfIn PDF document text
    • http://janjoling.com/public/ckfinder/userfiles/files/7748390141.pdfIn PDF document text
    • http://educaholistica.com/resources/img/imagesck/files/mikupofifegadi.pdfIn PDF document text
    • http://budgettranslation.hu/sites/default/files/file/dezewilubiviziz.pdfIn PDF document text
    • http://aumnat2car.com/ckfinder/core/connector/php/upload/files/tedep.pdfIn PDF document text
    • http://marthomaiticherukole.com/userfiles/file/tejatogiwuxemulotak.pdfIn PDF document text
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/03c86055b965ce038f28b4120f5485bb/92410733720.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/5df8860294330325475f0c4eccfe7443/wenadovixotiwimivino.pdfIn PDF document text
    • https://jordanadams.com/ckfinder/userfiles/files/73922618371.pdfIn PDF document text
    • https://dakhoathienhoa.net/images/files/66403332349.pdfIn PDF document text
    • http://beamstraffic.ae/amb/userfiles/file/jipapozalawedomutopub.pdfIn PDF document text
    • http://hit-air.pro/ckfinder/userfiles/files/luniwamusasidonovenamitan.pdfIn PDF document text
    • https://girilawfirm.com/content_files/files/girerupodiwitil.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/43e6ea53afba640c8b11e32da07a8f39/79500237751.pdfIn PDF document text
    • https://clicksnepal.grnca.org/img/files/files/detifupuvenix.pdfIn PDF document text
    • http://animationcoach.com/userfiles/file/molowotexikujate.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613939b3edd26---fitejukutaladukeziti.pdfIn PDF document text
    • http://sinoscaform.com/upload/ckimg/files/202109062224015421.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=fortnite+free+v+bucks+creative+map+codePDF 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_off0000e5a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5A8 18060 bytes
SHA-256: dce0fbe804b3850d741691467278ef2fa98c194fbfae8cd890d2609e01367d6d
font_01_sfnt_off000114b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114B5 11112 bytes
SHA-256: 8f5c474ca3c745ca2b75838ea122c5942faa3017f4e6788c9877dd7ea9106e0d
font_02_sfnt_off00012e75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E75 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1