Malicious PDF — malware analysis report

Static analysis result for SHA-256 751dcbe1d86cabfc…

MALICIOUS

PDF

75.1 KB Created: 2021-05-11 06:54:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: 07aa2053e32ae58d717e0628f1491f09 SHA-1: 669c67e46c838c10779de541794688090e19472e SHA-256: 751dcbe1d86cabfc0efa685dfa5c6738c17afff3a6accd8f41e9994bb57e5b2b
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm or redirection mechanism. The document body, though heavily obfuscated, appears to be a lure related to a medical condition, likely intended to trick users into visiting malicious URLs.

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 https://doellefjelde-mussemarked.dk/images/newsmail/file/sazokipumukijevomukeju.pdf In PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16089260e83520---82818482755.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/vo30ar00vg86ee59tafsvock42/pabadem.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607541e5936cc---17711497947.pdfIn PDF document text
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607f9be8aa84f---vavidonabapavidedevuroxi.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088dfac2e1aa---35691543577.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1608c5cac2826d---80302134551.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607e7fea18ee9---75877619545.pdfIn PDF document text
    • http://maidnheaven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d1a1ac9897---75146008161.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606ebc7eba89f---samabugi.pdfIn PDF document text
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/a036175e56b487a525076065e75b0202/27361084163.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608148a499cf3---pelumemukedefabemitinuvo.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/6d832cff789d77626ad7e26ddf980c62/31148214498.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/kilomefe.pdfIn PDF document text
    • https://aulacvn.com/upload/fck/file/24377306549.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=bacteriuria+asintomatica+en+hombres+pdfPDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d688.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD688 5432 bytes
SHA-256: 600eda11909ffa5c67d66eec1e346733fc7eaa5dab8d36723d4fbcb12e308e16
font_01_sfnt_off0000e8c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8C5 12012 bytes
SHA-256: 0308e79c3452ca48ca7b9c9c8d5f73903a490f852dd3c46c075fcf6d5991abda
font_02_sfnt_off00010f77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F77 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378