Malicious PDF — malware analysis report

Static analysis result for SHA-256 91ba2724861fa642…

MALICIOUS

PDF

85.2 KB Created: 2021-03-14 12:43:49 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 196f75f6ffc405f4858e273c7774df3b SHA-1: 83c98c650a0cbaee2433132415818d918fc70671 SHA-256: 91ba2724861fa6426626eeca83d2641a509a44a3eebce445d359133c0969d249
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with a high-confidence ML classifier and ClamAV detection indicating maliciousness. One prominent URL, 'https://vilenefex.ru/strik?utm_term=sid+meier%2527s+civilization%25C2%25AE+vi+gathering+storm+new+civilizations', is flagged as external and part of a link farm on disposable hosting, suggesting a phishing or malware distribution attempt. No scripts were extracted, but the PDF structure and URL patterns are indicative of a malicious document, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://vilenefex.ru/strik?utm_term=sid+meier%2527s+civilization%25C2%25AE+vi+gathering+storm+new+civilizations
    • http://sopesukenapad.scienceontheweb.net/duwuduzevepumubipajab.pdf
    • http://koprovk.xyz/sebedue4ycs.pdf
    • http://datinge.site/hardboiled_eggs_ovenjeiuc.pdf
    • http://osmosiotzs.fun/chelsea_fc_vs_watford_video9aj4w.pdf
    • http://dontbeshy.xyz/20775172596qxgzy.pdf
    • http://mattelipsticks.site/how_to_turn_off_everstart_jump_starterfxzgw.pdf
    • http://toppiksnack.xyz/how_to_clean_portable_ac_condenser_coils5ruoj.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/dazovosugev/python_for_loop_increment_index.pdf
    • http://xegeduv.rf.gd/canon_mx430_printer_ink.pdf
    • https://2ffa788b-df2f-461f-b9c5-573bec542745.filesusr.com/ugd/374ce0_89dddc62932841f68e84e09f67d7a082.pdf?index=true
    • https://s3.amazonaws.com/bamepofewalada/90500096608.pdf
    • http://vininotubosom.epizy.com/koxanaro.pdf
    • https://s3.amazonaws.com/mubefula/java_swing_gui_builder_free_download.pdf
    • http://marojinoz.rf.gd/homophones_worksheets_10th_grade.pdf
    • https://19e6fc83-c281-4d06-93fd-e8b16a02b90a.filesusr.com/ugd/ce5d00_cd2db05fc0db4f7bbb6f9cadcaca76cc.pdf?index=true
    • https://c7fb3737-a2fb-4e06-b71d-f78b648bb0a4.filesusr.com/ugd/a9248e_ae0102e79358497887ffe399b28ba151.pdf?index=true
    • http://fufudaloxola.onlinewebshop.net/53415056306.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_off00010907.bin
a7682f4ad39a3ef8d113bd4c8ff4c48479699fd0b349c874286951eb155c26f7
pdf-font-stream PDF embedded font (sfnt) at offset 0x10907 5936 bytes
font_01_sfnt_off00011d37.bin
2eebc1a2575529872fcbe9e4ed1f2b907d893acf5c9813b47e1ef568a68fc31d
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D37 12052 bytes