Malicious PDF — malware analysis report

Static analysis result for SHA-256 735eb69cb5d38bb7…

MALICIOUS

PDF

72.4 KB Created: 2021-05-05 16:09:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 8812cbe08a7ddf56698880d241534cbd SHA-1: a727eee7446d913c3013f041e44d29518b938170 SHA-256: 735eb69cb5d38bb726845443e3b10be5f76d4866ebe032387ab93478653e372c
194 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting, indicating a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to phishing or malware distribution sites. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 7

  • 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 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.
  • 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://xajibur.ru/strik?utm_term=how+much+is+storm+king%2527s+thunder PDF link annotation
    • https://ragurinibobuma.weebly.com/uploads/1/3/3/9/133986244/jekefuxaxabedime.pdfIn PDF document text
    • https://jadilibetaz.weebly.com/uploads/1/3/4/8/134871175/gabakum.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452382/normal_602268add6c0d.pdfIn PDF document text
    • https://regujimupakuve.weebly.com/uploads/1/3/5/3/135348903/bapuso.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4469378/normal_6029486a54e6a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4375073/normal_600635fe9a3d5.pdfIn PDF document text
    • https://repugololenip.weebly.com/uploads/1/3/4/8/134880500/sozuwipozetoto.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4465930/normal_5feb492238db1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470389/normal_60446f59369e0.pdfIn PDF document text
    • http://cuzinfo.ru/descargar_biblia_paralelazd1hu.pdfIn PDF document text
    • http://segway-wheelchair.ru/troy_bilt_tb110_idle_adjustment734ot.pdfIn PDF document text
    • https://pafebexazare.weebly.com/uploads/1/3/1/1/131163914/nagexepapoz.pdfIn PDF document text
    • http://xitnet.fun/sad_love_story_films_on_netflixgga2h.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/xukirizugukugi/como_pasar_de_centimetros_a_pulgadas.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c5f3233a-c1c3-411a-937f-c2c6b921e50b/pisapupetobebigeba.pdfIn PDF document text
    • https://s3.amazonaws.com/womirofop/avast_internet_security_2018.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ab12eed0-a5e9-430c-81b5-2091c7ecb85a/dunkin_donuts_multigrain_bagel_with_cream_cheese_calories.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c4cdcd0c-d2de-4d3f-9b04-bd296685e2f1/grade_3_science_worksheets_free.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2f6c8398-ecc0-4c22-bca0-74ac8fd7a02a/buwukivebulojewob.pdfIn PDF document text
    • https://s3.amazonaws.com/wapabefizosumi/homeostasis_and_negative_feedback_questions_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6e9112ec-3e39-410b-84d5-28027cd38199/4360836210.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4c92c487-2a53-4054-bf32-3d7dadbe33f2/garmin_nuvi_255w.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB03 5264 bytes
SHA-256: dbf52b3b368ab2d0af921d91796bd1e69618f36e6536aa4368fefea09e91b545
font_01_sfnt_off0000ecd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECD5 11204 bytes
SHA-256: 8edf9003039e137aaf49381b8fece01719851de7ce76e92ebde1f68aa62160ad