Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e44b15cbe9503dc…

MALICIOUS

PDF

79.8 KB Created: 2021-03-22 14:24:59 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: e91fe3de621edd41f74b8e360dc728cc SHA-1: cfc3d563a376850cc7511f2a1ebf61305121fc89 SHA-256: 3e44b15cbe9503dcb6083f40fced1a7ce41396f4e6aae265cc1ba039206b759f
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable hosting, and is flagged by ClamAV as a phishing trojan. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains references to 'Geronimo Stilton' and 'wkhtmltopdf', suggesting a lure to a malicious site disguised as content. No scripts were extracted, but the high number of external links indicates a phishing or redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 5

  • 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://xezojetit.ru/strik?utm_term=geronimo+stilton+season+2+episode+4 PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4497638/normal_5ff632e2da09c.pdfIn PDF document text
    • http://zinuxuf.22web.org/dmv_written_test_california_2019_answers.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481836/normal_6026451877ba1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414691/normal_60262aa60d971.pdfIn PDF document text
    • http://gakagebir.mypressonline.com/vadolipibusivilu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370294/normal_600af9bf27370.pdfIn PDF document text
    • http://tunabamilusi.mypressonline.com/bank_customer_service_representative_job_description_for_resume.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4469128/normal_5fd9d098b3daa.pdfIn PDF document text
    • http://wudaxozibutix.sportsontheweb.net/tawinufo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370077/normal_60303adfb63b4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405195/normal_60357ad0452c8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460266/normal_604dc22f520f4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378623/normal_6018a055c341a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366628/normal_6045e90130c59.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4413469/normal_5ff6684b0984b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4382627/normal_5ffbe16013c4f.pdfIn PDF document text
    • http://makebugobiwuka.mypressonline.com/xavezovufobeja.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448991/normal_602110349e3fd.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4380382/normal_5fdcd2dd62b33.pdfIn PDF document text
    • http://dizofuses.mypressonline.com/personal_statement_for_scholarship_application_examples.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4409113/normal_5fde75dea47ae.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371247/normal_605870e99d98b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427501/normal_5fea34c1a6df1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://zevovalik.epizy.com/denimifu.pdfIn PDF document text
    • http://sazojojuw.rf.gd/varuduvoz.pdfIn PDF document text
    • http://komusera.rf.gd/kusejowikepef.pdfIn PDF document text
    • http://puliwoxijulu.rf.gd/english_basic_grammar_test.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_off0000f688.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF688 5356 bytes
SHA-256: cb3b6f6e2cccb48eec13b95db122db84c14831984643a680e2c42f347a429f96
font_01_sfnt_off000108ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108AE 12192 bytes
SHA-256: 7666a2fa6cff0b9f5ef16c2fe20ee1b2f74e03eb9fcbaadbc5b040cb7fa172c6