Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf31df58b1133f9c…

MALICIOUS

PDF

76.1 KB Created: 2021-06-10 05:17:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 8739947a5dcb5bf172ced7e9af9b0d8c SHA-1: 12f7542566a08b025e64c1f291778c99cd1a7a55 SHA-256: bf31df58b1133f9c57ece0f78f33eb129ebf5a46492245893e9fe4bed79aadbb
156 Risk Score

Malware Insights

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

The PDF file contains numerous links pointing to compromised WordPress upload directories and disposable hosting sites, suggesting a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution, disguised as a download for 'Cars 3'. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or malware delivery campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://chcial.ru/uplcv?utm_term=cars+3+download+apk PDF link annotation
    • http://slsnn.ru/content/file/xugejusa.pdfIn PDF document text
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2660e2bc8---basokajir.pdfIn PDF document text
    • http://originalcheck.it/public/img_admin/file/%5C/kaxoxijodovalanefuwixel.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160a7aae920bbd---15321934836.pdfIn PDF document text
    • http://nappsa.org/userfiles/file/10663026309.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d5dac66984---dadifuxanom.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609d2a4c37d98---47948938742.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f76fdeb542---1375158995.pdfIn PDF document text
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/8e753953d3f2b8e0f238701f508ed233/10472216067.pdfIn PDF document text
    • https://fultoys.com/userfiles/93100288380.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160840adc3932a---wemunu.pdfIn PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/61a9342bd17aec0e6690153c3c1bbc10/2225216985.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/29209ad12b8d217b97c5ddae4e7b7470/12740114175.pdfIn PDF document text
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/c6qu6fh01ggo7cg1lvp5brbdr3/5831491667.pdfIn PDF document text
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/a1aa68517c6f66170b5b89a12376acde/sadegudo.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/b6fb37ddaa4bbc0c8e9b63b36f7ed19d/winoka.pdfIn PDF document text
    • https://medgarlci.com/wp-content/plugins/super-forms/uploads/php/files/2a8a9731d6ad38b2ec0a38c7d29c5697/89939142644.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eb56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB56 5180 bytes
SHA-256: dcfa428304d1d14a72750a22d785ba9a012f5ed4b81a3d66a693212d1ab86221
font_01_sfnt_off0000fd0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD0D 11872 bytes
SHA-256: 609cc5ecd510c9d125b929c4768918a5619adcb2afdfd6d42ea29d1af3767d2e