Malicious PDF — malware analysis report

Static analysis result for SHA-256 a13980dec44db861…

MALICIOUS

PDF

67.8 KB Created: 2021-03-14 17:52:42 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: f7a0bf84455bab2a0aedef5ca791eb05 SHA-1: ab67d47a248b043d61a9d7e82c2c56fa0cdca49d SHA-256: a13980dec44db8611a139d9e9ee47f4cc2f8627cce56691250d674839b9aae8f
186 Risk Score

Malware Insights

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

The PDF file is identified as malicious by ML classifiers and ClamAV, with a critical heuristic detecting a mass external PDF link farm on disposable hosting. The document body, though heavily obfuscated, contains text related to 'Kumon answer book', suggesting a lure. The presence of numerous external URLs, including one pointing to a potentially malicious domain, indicates an attempt to redirect users to further malicious content or phishing pages.

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://lozipotod.ru/wix?keyword=kumon+answer+book+i+math PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4457843/normal_5fef0e895f011.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444622/normal_5fd82611b76df.pdfIn PDF document text
    • http://tvoeobrazovanie.fun/dedisofabuk4f501.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4492272/normal_5ffe4af97ce7e.pdfIn PDF document text
    • https://zezevibowavaki.weebly.com/uploads/1/3/4/8/134854125/7381805.pdfIn PDF document text
    • http://swiss-family.space/puxiduvomofazelexztja.pdfIn PDF document text
    • https://wagigezo.weebly.com/uploads/1/3/0/7/130775958/leledawunolumap.pdfIn PDF document text
    • https://fenipedixov.weebly.com/uploads/1/3/5/3/135385823/9712003.pdfIn PDF document text
    • https://fugiweritukasuj.weebly.com/uploads/1/3/4/6/134682589/pidedupe_pugukedolebo_tavisiz.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489035/normal_6040d5ea4f492.pdfIn PDF document text
    • https://rudunusom.weebly.com/uploads/1/3/4/6/134602981/6605841.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369764/normal_60102e1098b47.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://kikanelomer.onlinewebshop.net/76817052965.pdfIn PDF document text
    • https://abbf68a8-5b21-4996-91be-11266bd273ed.filesusr.com/ugd/9374a7_b2656b64c0714140bdd0df0c5c63521f.pdf?index=trueIn PDF document text
    • https://a39ac558-8fe8-437d-9e10-dc9402d6cb9c.filesusr.com/ugd/1ebe14_3d9fd46105d14165b1599c31f122751f.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xoxaneral/gorubikazopapuxusixuvuzir.pdfIn PDF document text
    • https://b23183eb-b2e5-455e-bc25-91fac1efd10f.filesusr.com/ugd/cc14e4_88d99cc95c2345eaa9bc452632b0e766.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/kegovev/apa_6th_edition_academic_writing_guidelines.pdfIn PDF document text
    • https://f3dcd8e3-6656-4b47-a81e-a993d3c4f2a1.filesusr.com/ugd/aa9ef2_a4a9ea1ddc294685b3a1fde34219a349.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/lusabifef/lefagukesaginafu.pdfIn PDF document text
    • http://wutesejib.onlinewebshop.net/creative_sb_x-fi.pdfIn PDF document text
    • http://titugol.atwebpages.com/critical_theory_today_chapter_1_summary.pdfIn PDF document text
    • https://s3.amazonaws.com/potamotaz/idm_cracked_for_pc.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_off0000ce71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE71 5160 bytes
SHA-256: 81151ff20f4cc2aa46e2c5b3eea6020d83949fafcc3517f00207b8a4e6677f7d
font_01_sfnt_off0000dfe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFE0 9788 bytes
SHA-256: 0e440d17fd03b85530ee01f4e0e55f7423d40c267b8af77de92b9a0e7238c35c