Malicious PDF — malware analysis report

Static analysis result for SHA-256 83c45498abc575a7…

MALICIOUS

PDF

65.5 KB Created: 2021-01-05 22:00:31 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 5de14c2eec872fa63db9ec7c82ac9629 SHA-1: d7a6cb0215d04e418bc2fbfca5adfa458ab654ad SHA-256: 83c45498abc575a74739d7ac7dd56cb5c9d0ce52fcd8122352d7916696387f0e
186 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier with high confidence. It contains a large number of external links, many pointing to disposable domains, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and contains metadata indicating it was generated by wkhtmltopdf, a tool often used to create PDF documents from web content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://trafffi.ru/aws?utm_term=xie+xie+chinese+chess
    • https://static.s123-cdn-static.com/uploads/4480891/normal_5ff24f63605dc.pdf
    • https://diwefiramogepot.weebly.com/uploads/1/3/4/2/134265367/c5478336cc.pdf
    • https://dedezeke.weebly.com/uploads/1/3/4/4/134494225/5127170.pdf
    • https://dojufewuwi.weebly.com/uploads/1/3/4/2/134235401/detutux-roxikukorivefav-dazelevof.pdf
    • https://kazigujexumakul.weebly.com/uploads/1/3/4/3/134320364/gogaguf.pdf
    • https://rajidorux.weebly.com/uploads/1/3/1/4/131453086/b95e60fac3c43dd.pdf
    • https://cdn-cms.f-static.net/uploads/4376858/normal_5f89ae476e64b.pdf
    • https://vetovevigu.weebly.com/uploads/1/3/4/4/134486276/lidajonugizat-larixe-bomom-soxib.pdf
    • https://pemugaladesav.weebly.com/uploads/1/3/5/3/135307247/f6c2ca.pdf
    • https://pinozawekik.weebly.com/uploads/1/3/4/5/134589254/segatabawupo-befen-jumoxen.pdf
    • https://cdn.sqhk.co/woxezelej/jdieAFd/509021561.pdf
    • https://funefazadoma.weebly.com/uploads/1/3/4/6/134648765/foxuvabaxigu_wewokuvov_duvebemitizi.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/8f66027b-a550-4fbe-b628-fe7ee294192b/12432551063.pdf
    • https://uploads.strikinglycdn.com/files/e807618e-9448-4639-9d36-700e346cfebd/trackaddict_external_camera.pdf
    • https://uploads.strikinglycdn.com/files/18353be2-f13e-4927-97e4-45435ddd9f2e/mufezivok.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c4bf.bin
d56653fa28f504f79d6568a586795792d663ce548a286bfd8ae979640f486f48
pdf-font-stream PDF embedded font (sfnt) at offset 0xC4BF 4596 bytes
font_01_sfnt_off0000d462.bin
0d849ff7952c05f2715c8f611de10d93f0c5ea64d64a5a5e1b3f18509fae6e87
pdf-font-stream PDF embedded font (sfnt) at offset 0xD462 11760 bytes