Malicious PDF — malware analysis report

Static analysis result for SHA-256 f28a09a75ab5ab0f…

MALICIOUS

PDF

88.0 KB Created: 2021-03-01 01:30:40 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: aabf06124ec699d72adb3e523fd08f36 SHA-1: 084aabcde296585f26462e5d41d27b1059ebd1af SHA-256: f28a09a75ab5ab0f622008b8c46818f536fc427ce20e013e804c184b35c8d74c
186 Risk Score

Malware Insights

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

The sample is a PDF file flagged as malicious by ClamAV and an ML classifier. It contains a large number of external links, many pointing to disposable hosting, indicating a link farm or SEO manipulation tactic. The document body is heavily obfuscated but contains references to 'wkhtmltopdf' and a date, suggesting it was generated programmatically. The presence of numerous external URLs suggests an attempt to redirect users to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • 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.
  • 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://bologen.ru/wix?keyword=little+tikes+cube+climber+assembly PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4444110/normal_6012284db1733.pdfIn PDF document text
    • https://cdn.sqhk.co/fevazufalul/jCUgdij/genazesuronuxogeze.pdfIn PDF document text
    • http://masterpowerpoint.com/ae_dil_hai_mushkil_full_movie_downloknebl.pdfIn PDF document text
    • https://pubategikosiw.weebly.com/uploads/1/3/4/1/134131453/ratovuworelelijujux.pdfIn PDF document text
    • http://bupro.asia/is_there_a_season_2_of_epix_war_of_the_worlds9tvcc.pdfIn PDF document text
    • https://cdn.sqhk.co/jabosuve/sbieAVY/mini_woodturning_lathe_uk.pdfIn PDF document text
    • https://pepevifive.weebly.com/uploads/1/3/4/4/134480859/roxubaloru_wapuru_wikavof.pdfIn PDF document text
    • http://xidasetetobuge.scienceontheweb.net/xidaxonutubogubikozevupem.pdfIn PDF document text
    • http://btsworld.org/460062961388jj6l.pdfIn PDF document text
    • https://cdn.sqhk.co/fumamimed/mHrPhfL/fm_17_wonderkids_cheap.pdfIn PDF document text
    • https://cdn.sqhk.co/baresupujar/ieheEje/jisapulijurerovugexidef.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470401/normal_601ae36516885.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413566/normal_600c3cc1e8cea.pdfIn PDF document text
    • https://tejojapifofomo.weebly.com/uploads/1/3/4/3/134339563/fotoxejoje-fesusituk-wepavepupo.pdfIn PDF document text
    • https://bekajujoxofutit.weebly.com/uploads/1/3/1/4/131406668/c7841.pdfIn PDF document text
    • http://vopugixeroramox.medianewsonline.com/yoga_vasistha_books_in_telugu_free_download.pdfIn PDF document text
    • https://cdn.sqhk.co/vusutazomaga/ejbhgjU/online_photo_editor_for_dv_lottery_free.pdfIn PDF document text
    • https://likifovufuli.weebly.com/uploads/1/3/4/5/134588617/dowoguxu.pdfIn PDF document text
    • https://cdn.sqhk.co/fegujajox/icmFhaZ/ralikiguxuzap.pdfIn PDF document text
    • https://cdn.sqhk.co/xuwolupenilu/ZgjjjhZ/banego.pdfIn PDF document text
    • https://cdn.sqhk.co/zudilubal/95gcNsL/bubble_freedom_mod_apk_unlimited_money.pdfIn PDF document text
    • https://cdn.sqhk.co/jetirivotu/Jp0giRo/piezo_buzzer_arduino_tinkercad.pdfIn PDF document text
    • http://sixesijilolun.mywebcommunity.org/how_much_do_merchant_navy_get_paid.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://vujuvisesakok.myartsonline.com/an_astrologers_day_questions_and_answers_class_11.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_off00011a7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A7E 5192 bytes
SHA-256: a520d3a91fbfec9c33929ea863dc4c5f556f1de1d76c6c78f99b649497933bc4
font_01_sfnt_off00012c1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C1D 11088 bytes
SHA-256: 19d55edb94b66ad7dabea08efcd5c3ec3d700c599676b1565a7341d9fc3edaa7