Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ba97a873bba4ebc…

MALICIOUS

PDF

72.1 KB Created: 2021-03-18 00:04:12 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 4bd470018480f9f3a45718db4cb3f6a7 SHA-1: 2b176ff68b47c4ff8dc504baeece94ad3c94fd2d SHA-256: 8ba97a873bba4ebc03e27df59e353bd58c6122a15ff7ed86c9e93aa887556b4d
244 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier, and contains numerous embedded links. One critical heuristic indicates that the PDF links to known malicious redirector infrastructure, specifically `https://dafemum.ru/strik?utm_term=cuanto+vale+un+metro+cubico+en+litros`. The document body is heavily obfuscated, but the presence of a link farm suggests an attempt to direct users to potentially harmful external sites, aligning with phishing or SEO manipulation tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://dafemum.ru/strik?utm_term=cuanto+vale+un+metro+cubico+en+litros In PDF document text
    • https://lomofoxagut.weebly.com/uploads/1/3/4/5/134524577/84fe40.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4491686/normal_60507d1dd57c2.pdfIn PDF document text
    • http://fagumawegoleleb.mypressonline.com/mens_health_workout_programs.pdfIn PDF document text
    • https://cdn.sqhk.co/jomububorava/ijhfS52/muvedezenipisinapo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374002/normal_6024764655aae.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4485826/normal_5fe34b5fc8860.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4462096/normal_5fff3e6ebfdea.pdfIn PDF document text
    • https://cdn.sqhk.co/rajexizeba/Ficuegd/23026999919.pdfIn PDF document text
    • https://cdn.sqhk.co/vumatoxikom/5icayqt/bowling_3d_strike_free_download_for_pc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480878/normal_60375997f2268.pdfIn PDF document text
    • https://cdn.sqhk.co/xovujiroveg/gFAblib/42601213998.pdfIn PDF document text
    • https://veguxalefimas.weebly.com/uploads/1/3/1/3/131382166/luwozafuzuv-lozunotazokajo-lakip-woluraxe.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/5bf3ed63-c909-4ef3-8cbf-8297eee1287f/18863398149.pdfIn PDF document text
    • http://penanaras.myartsonline.com/beauty_by_jane_martin_symbolism.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/579f28e7-a511-44d7-a6bf-8e545b033258/hamlet_act_4_scene_5_summary_shmoop.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/99505ca5-7d15-433b-a656-d03d62526652/visarodud.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5c61abf7-cb6a-4092-8161-4b3290dc2008/the_theory_of_moral_sentiments_summary.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/758649af-c293-441d-85f9-b9e85d41ff87/92071976261.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/867b6185-8015-4df7-9493-acde51fa6fe2/fimutak.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_off0000dab9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAB9 5048 bytes
SHA-256: 64d1c7c3ede2c620c8fd565c0601b4acc0ee023d0d2381bfc949dbc4fecc7013
font_01_sfnt_off0000ebcd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBCD 11984 bytes
SHA-256: 592e072e187b8db9713d6bef782aaab7db4d97a4ebd0d9d765567fd89fade4e3