Malicious PDF — malware analysis report

Static analysis result for SHA-256 79a6be166b7add43…

MALICIOUS

PDF

66.2 KB Created: 2021-06-18 12:49:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 0641ab90b0256fd572490e978601c144 SHA-1: a9926aed30278345a5e344520fb2bcb2a02b0be4 SHA-256: 79a6be166b7add437d7193810df3a05fe7e37e8a7a4707effe1c3c64bb380159
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file is a PDF that contains numerous links, many of which point to compromised WordPress sites hosting PDF files. The document body, though heavily obfuscated, suggests a lure for a "Buffettology workbook pdf free download". The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1fd85e1f03---47902625162.pdf In PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/43d2a90d70c984e7e5792acd68943047/40210984344.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/ca667e33e2f333807866572803dcab0f/15459611453.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/160985c951fbbf---53739850570.pdfIn PDF document text
    • https://avonsteel.com/UserFiles/file/sudiretarutemiv.pdfIn PDF document text
    • https://ckmandarin.com/uploads/fuxif.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b749ea4f0d---rixeke.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a6a69aa89c---zobolitaxux.pdfIn PDF document text
    • https://www.anandtirth.com/wp-content/plugins/super-forms/uploads/php/files/7rpecvo04ssbj97i6207qc4h61/godegiwitu.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1609c67e624732---86942629780.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/a81bdddb8b2da031ea1fd0f0f206061b/bezudenuvejovemogelezat.pdfIn PDF document text
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/d97b6034e92afd4901b97fe7163cb64b/gufoxililijivasisaju.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/9814dd3cede8ca1242b3db665cd75399/sebuxewemipebuzuv.pdfIn PDF document text
    • http://spoanalyze.com/wp-content/plugins/super-forms/uploads/php/files/7be355e496f372bff974d1e20174d9b6/golas.pdfIn PDF document text
    • https://elitstroycraft.ru/source/file/77742354347.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/ae2mehnikpl2kacdtkpdkehlhq/zonibuvagoluv.pdfIn PDF document text
    • http://domholidays.com/userfiles/file/rarusulipodaw.pdfIn PDF document text
    • https://k2salight.com/wp-content/plugins/super-forms/uploads/php/files/cddc2d10ca1bcfdeb58a7598e02d6b04/karoxumukusemeweze.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/2j96mag6ssc48on0pktdrbqhj0/2973639917.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=buffettology+workbook+pdf+free+downloadPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b889.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB889 5476 bytes
SHA-256: 31bc905a7619803ac0376524001de4efdf93bff8e8a86a4d2a13356dcd5da522
font_01_sfnt_off0000cb55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB55 20512 bytes
SHA-256: 677ae916fceb91d2683ad4e73b2089cbdabc0d641145632f0ce2f345abc50342