Malicious PDF — malware analysis report

Static analysis result for SHA-256 792b671ed175c4cf…

MALICIOUS

PDF

81.1 KB Created: 2021-10-06 13:53:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 499e9081f71636b152835536174c834d SHA-1: f8f0be8307a8a88b0d5915cc7c2f57d8a9ba09d8 SHA-256: 792b671ed175c4cf8c037ecac9042273bdc4bba8ef9bcf72feea167e2d845e25
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which are associated with compromised WordPress uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the embedded URLs and the 'link farm' heuristics point towards an attempt to leverage external resources for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://irlanc.ru/uplcv?utm_term=what+to+do+if+you+feel+nauseous+after+eating PDF link annotation
    • http://xiangzhuan.tw/upload/files/4084355906.pdfIn PDF document text
    • http://hieuchuan.com/upload/files/gezevebulelubom.pdfIn PDF document text
    • http://www.feniuniversity.edu.bd/app/webroot/ckfinder/userfiles/files/pogin.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/1c141527e1aa7d034a41d73163cc381f/sanolamimud.pdfIn PDF document text
    • https://rowadalbyt.com/userfiles/files/53521129599.pdfIn PDF document text
    • http://franzoesischebulldoggen.eu/userfiles/file/58135413318.pdfIn PDF document text
    • http://iccj.jp/images/uploads/fckeditor/file/22792855047.pdfIn PDF document text
    • http://kahasat.cz/data/file/97257742843.pdfIn PDF document text
    • https://venusnvs.com/userfiles/file/98725044980.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615169f3c9859---96313576881.pdfIn PDF document text
    • http://www.bc-arman.kz/ckfinder/userfiles/files/nunekaso.pdfIn PDF document text
    • http://jmvlpslimited.com/ci/userfiles/files/76322032378.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/1615d66a04796e---96589815241.pdfIn PDF document text
    • http://iwilldoit.ru/uploads/files/files/58075337495.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/2473858201.pdfIn PDF document text
    • http://oticonshop.net/ckfinder/userfiles/files/65858446290.pdfIn PDF document text
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/d0c72b76c0620d5b9285466932b74128/fugunugaxamavigefewe.pdfIn PDF document text
    • https://mmagame.com/userfiles/file/71874654579.pdfIn PDF document text
    • https://ctcitsupport.com/media/files/sixosipoligikuje.pdfIn PDF document text
    • http://ximangsongthao.com.vn/app/webroot/uploads/files/10829682190.pdfIn PDF document text
    • https://nabsangram.com/userfiles/file/lezuwabonokolaje.pdfIn PDF document text
    • https://hobbypet.cz/files/file/mobemojewazapikilorazef.pdfIn 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://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_off0000d29f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD29F 18900 bytes
SHA-256: 2e512c2322034269f6e6bf7a0a72dfe4637af1fdf42b134c9ed8e6331998dafc
font_01_sfnt_off000103c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011bdc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BDC 10840 bytes
SHA-256: 3cae23e576a852504f6ee92c7c28927f74030b4c44af96647b1b985a8919d511