Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d49804392d7e949…

MALICIOUS

PDF

76.5 KB Created: 2021-06-03 12:50:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 76af66ca9f2e4b6c2b052e853119f97d SHA-1: c4b43bf958faa88a4e4b86ea09c101f554662da3 SHA-256: 8d49804392d7e9493114b678ca79f1aa8f9a42d43b3df7ed8a1957b4e40707d7
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 0.9992

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://wastran.ru/pbw?utm_term=libro+de+lecturas+tercer+grado+1993+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4479705/normal_5ffc9db075260.pdfIn PDF document text
    • https://fomimelagesuto.weebly.com/uploads/1/3/1/4/131406840/8994704.pdfIn PDF document text
    • https://saxipapes.weebly.com/uploads/1/3/0/7/130738636/926314.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4483851/normal_6005de16a4495.pdfIn PDF document text
    • https://zupufirelerige.weebly.com/uploads/1/3/0/9/130969681/62f84.pdfIn PDF document text
    • https://vuxemirisem.weebly.com/uploads/1/3/1/4/131453034/582c742a053.pdfIn PDF document text
    • https://farunigi.weebly.com/uploads/1/3/4/7/134716297/a3dddb23b26689d.pdfIn PDF document text
    • https://papunagaku.weebly.com/uploads/1/3/1/3/131384156/savekuz.pdfIn PDF document text
    • https://zukedobawalot.weebly.com/uploads/1/3/4/5/134526307/rusukemepiz_pubozig_bikoxugaluxos_bunobiwunexafa.pdfIn PDF document text
    • https://zufuzoxosuf.weebly.com/uploads/1/3/4/5/134500743/9299814.pdfIn PDF document text
    • https://lesinagin.weebly.com/uploads/1/3/1/4/131454304/jurutuvokefes.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386354/normal_60361c5112f42.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://mulasamesi.pbworks.com/w/file/fetch/144501447/77177177053.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b7b410d8-1649-48b0-a7c5-6894fb3d71a3/bekifatuzatatamadire.pdfIn PDF document text
    • http://memofemovo.pbworks.com/w/file/fetch/144436416/how_does_covid_19_affect_student_life.pdfIn PDF document text
    • http://nusuwoxub.pbworks.com/w/file/fetch/144414234/anlisis_del_cuento_el_otro_yo_de_mario_benedetti.pdfIn PDF document text
    • http://kufavuva.pbworks.com/f/why_did_my_grandfather_clock_stop_chiming.pdfIn PDF document text
    • http://bevojoluvu.pbworks.com/f/a_cincia_para_ficar_rico_bob_proctor.pdfIn PDF document text
    • http://jitijaloj.pbworks.com/f/what_is_a_bachelor_degree_certificate.pdfIn PDF document text
    • http://subazim.pbworks.com/w/file/fetch/144546468/kuwarolukukimalowidiw.pdfIn PDF document text
    • http://niwomif.pbworks.com/w/file/fetch/144426798/8823306598.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9d470ec0-d5ae-467e-86de-2f2f1b6037fd/organizacion_administrativa_de_una_empresa_ejemplo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/13c0077a-bf93-45e2-909c-042eafed46dd/hundreds_chart_mystery_picture_halloween.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_off0000e98e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE98E 5776 bytes
SHA-256: 6c35a48b1af13c41a7c80d2721644fd5e176641a3ec4391a458079741054ea74
font_01_sfnt_off0000fd46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD46 11464 bytes
SHA-256: c16761c103614703c827c0b5ddc4c72ced66db4bcdebbc590e0c99da701cdc09