Malicious PDF — malware analysis report

Static analysis result for SHA-256 b63273522b5a8154…

MALICIOUS

PDF

81.5 KB Created: 2021-05-09 05:16:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 73fe1ac6823a4c8225d488c31dc87fd0 SHA-1: e69ff2a0b2e7dab01042c8f63995b53b264f671f SHA-256: b63273522b5a815404ef92a0bc9687d3e551a176b91cf4d1a207cf32866e0298
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://baarspo.ru/strik?utm_term=denon+avr+x4000+bluetooth PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4413862/normal_5fe810777132e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478137/normal_6068de2a8c8af.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408976/normal_6009d88e8a069.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4499282/normal_5ff1c7995c074.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466657/normal_600a3ad7354af.pdfIn PDF document text
    • http://xujofalidubof.iblogger.org/renorutalepizubunaviz.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4393761/normal_5fc9123c76bba.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386609/normal_60185dc7c76d5.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4387933/normal_6008f2403c4cf.pdfIn PDF document text
    • http://gonakasuzoze.22web.org/japanese_sentence_patterns_for_effective_communication_download.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451555/normal_6034c9bd868f9.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://3e3188f7-d9e9-48da-9af6-4e6760718ee0.filesusr.com/ugd/4f7562_5e95d339db69431e8a5502f2a0caaa57.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/risalenefazozo/mekejidutomatifemosageju.pdfIn PDF document text
    • https://s3.amazonaws.com/kizugokofo/para_que_sirve_el_magnesium_oxide_420_mg.pdfIn PDF document text
    • https://b0c090b1-cb02-46d8-8a69-3fb9d82636b6.filesusr.com/ugd/4dbf3f_2f24babe8d7443b79525dc730c42f6f3.pdf?index=trueIn PDF document text
    • http://rakorexifaxokur.rf.gd/3_phase_induction_motor_construction_and_working_principle.pdfIn PDF document text
    • http://rotigolas.epizy.com/fema_egrants_user_guide.pdfIn PDF document text
    • https://b46c4cda-4951-41c0-816f-bbf02eee4d9b.filesusr.com/ugd/4ff992_fd4483b05ba3441894eeb90b0d3a758b.pdf?index=trueIn PDF document text
    • http://wobevewewa.epizy.com/33070447396.pdfIn PDF document text
    • https://a3c35cc3-4a3f-4d41-ab51-8b3e4b114d30.filesusr.com/ugd/2b25b5_92c0d4c2cbdf4ea49f9f7675105e332d.pdf?index=trueIn PDF document text
    • https://4fcc26ae-a476-48f2-98aa-cdc5c12f4544.filesusr.com/ugd/32d0e1_12655a72d4d945efad029206fd2d5a22.pdf?index=trueIn PDF document text
    • http://lerojijegomukuv.rf.gd/dufopigetafufomuz.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_off0000f857.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF857 5092 bytes
SHA-256: c0526c00e0d6735ee2f6c57a1e6af982cbe7138b4692b2c8916ace128baa3e12
font_01_sfnt_off000109ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109AB 15100 bytes
SHA-256: 0186f2d08dc64e8c3dd51a8fbdc1721744e1f02f6391e5973c5fad1918aaa70e