Malicious PDF — malware analysis report

Static analysis result for SHA-256 b56052c3d9e4c1b3…

MALICIOUS

PDF

83.5 KB Created: 2021-04-04 21:43:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 459f3f49585db2e05aa0e8c915f37685 SHA-1: c8e65d63ed219b5faebb01cfd9a6a18459c28199 SHA-256: b56052c3d9e4c1b3aff4aaf8bb7924322cc821b6b8f26c9d414fcb0d1a9456f8
186 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 domains, indicating a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://baarspo.ru/award?keyword=curso+de+bambuterapia+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4484636/normal_5fdc39005fe45.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4461767/normal_6045f7f727f4e.pdfIn PDF document text
    • http://gemajelibetojup.scienceontheweb.net/tp_link_access_point_configuration.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4479210/normal_5fe0f9f00b391.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380393/normal_60670103a92c2.pdfIn PDF document text
    • https://cdn.sqhk.co/fowipovoji/jdhiwhb/word_family_worksheets.pdfIn PDF document text
    • https://gosabejeda.weebly.com/uploads/1/3/1/4/131453015/guvibu-vokusakuma-tisipiwutukal.pdfIn PDF document text
    • http://faripofijukevom.mywebcommunity.org/onkyo_tx-nr626_subwoofer_setup.pdfIn PDF document text
    • https://cdn.sqhk.co/rajemaramiw/eqnTfhg/95829714282.pdfIn PDF document text
    • https://cdn.sqhk.co/fiduzosi/eifjgDs/pubozewesa.pdfIn PDF document text
    • http://xafopawiki.medianewsonline.com/55311378260.pdfIn PDF document text
    • https://rowurasivove.weebly.com/uploads/1/3/4/3/134357219/616fa3ef60.pdfIn PDF document text
    • https://wededizopi.weebly.com/uploads/1/3/3/9/133986349/1020967.pdfIn PDF document text
    • https://cdn.sqhk.co/jenotefi/ia8jhih/music_player_app_for_samsung_tv.pdfIn PDF document text
    • https://cdn.sqhk.co/moturalogupe/bVhdXVV/palozimemo.pdfIn PDF document text
    • https://cdn.sqhk.co/bikegola/T6ehg8U/27462824204.pdfIn PDF document text
    • https://vixojuderapu.weebly.com/uploads/1/3/2/3/132303060/9853feaf9245cd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4406516/normal_603f858486725.pdfIn PDF document text
    • https://cdn.sqhk.co/noloxunipe/gLajjjc/21315384608.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://pejemevogoge.myartsonline.com/23844690696.pdfIn PDF document text
    • http://kususen.myartsonline.com/22241553554.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f880.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF880 5096 bytes
SHA-256: e657304cf404bb8d1e2aaf872e132aadedf2d084dfca1fbc7013af617da5d412
font_01_sfnt_off000109d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109D2 12024 bytes
SHA-256: 9eafc8a06e8e17c63761017686e4136469cc7f19502d7a1b29cf17f7e82341e9
font_02_sfnt_off00013100.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13100 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3