Malicious PDF — malware analysis report

Static analysis result for SHA-256 b693720327815911…

MALICIOUS

PDF

67.8 KB Created: 2021-09-25 03:58:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7e677efc0a717056e629d68688846097 SHA-1: 1b922ab5998dc8a336241cfb963b4a8a085788eb SHA-256: b693720327815911d6c8e7c5bd3f91cf1d5fd804b12053519d5cda81c13c5f2f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF file flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised WordPress uploads and disposable hosting, suggesting a link farm designed to obscure the ultimate destination. The primary attack pattern involves luring users through a malicious attachment to a site that likely hosts further malicious content or exploits.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://maremio.ru/admin/ckfinder/userfiles/files/42125148179.pdf In PDF document text
    • http://indel.sk/userfiles/file/foxumulifikot.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16139553c5ac3d---vadiwamateguze.pdfIn PDF document text
    • http://xsteelstock.com/d/files/linuxugonisom.pdfIn PDF document text
    • http://ondamarinarest.com/upload/files/kedizimonosizab.pdfIn PDF document text
    • https://rmduncanrealty.com/userfiles/files/ligojugonagaja.pdfIn PDF document text
    • http://lapawan15.com/shop/fck_file/file/22660861223.pdfIn PDF document text
    • http://tajesink.com/Uploadfiles/files/52600695846.pdfIn PDF document text
    • http://net-marketing.hu/images/files/xosokunikig.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/c940a069cf062c631aeeb49952895b0e/bexixu.pdfIn PDF document text
    • http://bolshunoff.ru/images/wysiwyg/file/18242716239.pdfIn PDF document text
    • http://hzbmsj.net/images/upload/File/mimutojebisivijobisekir.pdfIn PDF document text
    • http://atmaircenter.com/lb/userfiles/files/gonujazuvurukiridafadoduk.pdfIn PDF document text
    • http://cuuhoatudong.com/upload/files/6531592617.pdfIn PDF document text
    • https://burstallconrad.com/editor_files/file/kegebulefipejosifemit.pdfIn PDF document text
    • https://portalkucharski.pl/app/webroot/media/files/kejevijobedewezekilelunu.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146948f1122e---xidijokavajurazokevivu.pdfIn PDF document text
    • http://sghr.ca/upload/ckfinder/files/74287984978.pdfIn PDF document text
    • http://m-camper.ru/ckfinder/userfiles/files/zukabinorixukosoxuz.pdfIn PDF document text
    • https://0286869143.com/editor_images/files/zirazilulobogu.pdfIn PDF document text
    • http://doudou.tw/userfiles/files/42617788116.pdfIn PDF document text
    • http://forglass.sk/userfiles/file/4286373309.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=ninnila+ninnila+movie+watch+onlinePDF 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_off0000accd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xACCD 10356 bytes
SHA-256: 3645db567955eb86a3055589a5c9e0f764a1b814cd55061f457cfb722d275fa5
font_01_sfnt_off0000c400.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC400 14496 bytes
SHA-256: 1ba66aa2b11d5b1e7a9ab65d3229ec763ead424b7a02240438b5e6aebebec640
font_02_sfnt_off0000e7eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1