Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c819c42cad383c2…

MALICIOUS

PDF

74.9 KB Created: 2021-05-14 21:57:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 6990e1bf5dbd53f684a64f71e548ea14 SHA-1: 6e18adb800ff488fd49bd582e439c1c889db3df6 SHA-256: 9c819c42cad383c2fcb10ec1eca140cbe729c0374ddce7796f24bff4d3fff5d0
184 Risk Score

Malware Insights

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

The PDF contains embedded links pointing to malicious redirector infrastructure, specifically 'https://dafemum.ru/strik?utm_term=john+deere+345+hood+repair'. Heuristics indicate this is a malicious redirector and a link farm on disposable hosting, strongly suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection further confirm its malicious nature.

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
  • 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 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=john+deere+345+hood+repair In PDF document text
    • https://static.s123-cdn-static.com/uploads/4384026/normal_60018104027d3.pdfIn PDF document text
    • https://dudafizegananif.weebly.com/uploads/1/3/4/8/134864336/dagagile_kujaf.pdfIn PDF document text
    • http://zonafuluza.iblogger.org/remizujos.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367299/normal_605fb4840c244.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412588/normal_606e59c3ee509.pdfIn PDF document text
    • https://bodonoweti.weebly.com/uploads/1/3/1/8/131856710/37f10e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404296/normal_60280d2bc19b5.pdfIn PDF document text
    • http://kasyanbeauty.com/914897392381gtnc.pdfIn PDF document text
    • http://mimivudarevi.scienceontheweb.net/equations_with_algebraic_fractions_worksheet.pdfIn PDF document text
    • http://vevufilusik.scienceontheweb.net/iso_9001_internal_audit_procedure.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460688/normal_6020d2b99104e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424009/normal_602f11f99de5d.pdfIn PDF document text
    • http://phrensy.co/how_much_weight_can_a_15_hp_outboard_pushfnolq.pdfIn PDF document text
    • http://kemedejovon.getenjoyment.net/apprendre_francais_en.pdfIn PDF document text
    • https://lapefobok.weebly.com/uploads/1/3/4/6/134663543/zoxebima.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fepoxojosatomu.epizy.com/75803213177.pdfIn PDF document text
    • http://lufiwivumijej.myartsonline.com/lutalonusum.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_off0000e76c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE76C 5204 bytes
SHA-256: af82caa745d56d1dc3c166135f35bf8627b0d151139d5ed55ef4214ba18ae8ef
font_01_sfnt_off0000f91b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF91B 11044 bytes
SHA-256: 675428102d3eb96134b77110ac343649c7282d47312e7915ee6155debab91989