Malicious PDF — malware analysis report

Static analysis result for SHA-256 8751f31e4220d485…

MALICIOUS

PDF

80.4 KB Created: 2021-09-07 22:19:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 1090b4d09bc5d25b64296c4d9aff1972 SHA-1: d94f5ecaa311a44ce22aa2c793b1fd2e0a1a6eb4 SHA-256: 8751f31e4220d485c986662f4211f088c97b078b04a24cf3698e4e23370ab0b1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Static analysis reveals it functions as a link farm, with numerous embedded URLs pointing to various domains, many of which are hosted on compromised CMS platforms. The primary purpose appears to be redirecting users through a network of links, potentially for SEO spam or to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/9afd58e730c0c1ef5e5d2e7080f204e7/50687025413.pdf In PDF document text
    • https://gabinetpro.pl/kosmetyczka/krakow/files/93679818151.pdfIn PDF document text
    • http://arcadia1973reunion.com/clients/3/33/33cb7023d77084166ed027ca16b579b7/File/gomijuranozugu.pdfIn PDF document text
    • http://songhakbbq.com/uploads/files/vanapemebozo.pdfIn PDF document text
    • http://short-story.ru/upload/file/rusobokal.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/16100e06244a12---79252403890.pdfIn PDF document text
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/9d1386054d4257b194a8dc667673a299/kagodonisidutibuzigavesuj.pdfIn PDF document text
    • https://biblioteka-koneck.pl/ckfinder/userfiles/files/xinazil.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/27302015675.pdfIn PDF document text
    • http://hotelbellevuepalermo.com/userfiles/files/kuwedasobemitobiku.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610108e7689b5---volin.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/1pboouddga3bhf8md6k2muocib/11965275682.pdfIn PDF document text
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/f6903dc2fc3782d3bb8397edee168447/58148496290.pdfIn PDF document text
    • https://relaxbotanika.cz/ckfinder/userfiles/files/jirapisopexobigal.pdfIn PDF document text
    • http://legalinet.eu/userfiles/files/76204644391.pdfIn PDF document text
    • https://2-view.org/home/view/public_html/ckfinder/userfiles/files/vatelijabalib.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ec42ba2e245---88310513293.pdfIn PDF document text
    • http://acpiindia.com/userfiles/file/19985180828.pdfIn PDF document text
    • http://anhhieu.vn/hinhanh/file/digabiwukudosovoxu.pdfIn PDF document text
    • https://www.erenang.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cf7f50ecf1---80758403530.pdfIn PDF document text
    • https://salvatoredivilio.it/userfiles/file/jipixapapivunaw.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab3a74936a2---8205605968.pdfIn PDF document text
    • https://steammining.com/userfiles/file/57079392207.pdfIn PDF document text
    • http://firegallery.ru/img/upload/6202881371.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=coma+mixedematoso+pdf+elsevierPDF 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_off0000d2d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2D2 10752 bytes
SHA-256: 5483bc21027b4d8fc93add1eb9b12ba32aab111c391eb310c275d7d07aaec404
font_01_sfnt_off0000eb9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB9E 18480 bytes
SHA-256: 79d3f565b37e2d7ff164a296843c49cca2a541f6ff4521feef98ce08155583ba
font_02_sfnt_off00011b80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B80 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1