Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fb0417e24d59057…

MALICIOUS

PDF

76.4 KB Created: 2021-03-16 20:12:40 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: d9ec95fb6190d326fa1c957ffe80ef4f SHA-1: d68d0d194d1a6f4c4f3bc0d7364b0fee3b70ab98 SHA-256: 8fb0417e24d59057189e412bf3aea02bd35b7560276b7b7146191cb390be625c
186 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning model indicated a high probability of maliciousness. It contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to redirect users to malicious sites. The document body, though heavily obfuscated, appears to be a lure related to educational worksheets, likely intended to trick users into clicking on the embedded malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://seumenha.ru/123?utm_term=balancing+equations+worksheet+middle+school+pdf PDF link annotation
    • https://zopokirupinurow.weebly.com/uploads/1/3/1/3/131381130/jabovurevol.pdfIn PDF document text
    • https://nenafusorez.weebly.com/uploads/1/3/1/4/131453248/suxum-vemuvisu-wotomojibo-tabela.pdfIn PDF document text
    • https://juxipibofo.weebly.com/uploads/1/3/5/9/135985723/ruxawamovum.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4403683/normal_5ffa7e7b803e8.pdfIn PDF document text
    • https://rijopadanag.weebly.com/uploads/1/3/1/0/131070137/xeposulaxobinunofumi.pdfIn PDF document text
    • https://xuwogufovesuvem.weebly.com/uploads/1/3/1/4/131406895/sadiwawuxovijikox.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4462035/normal_5fc877abbcd09.pdfIn PDF document text
    • https://cdn.sqhk.co/xagunetoxa/gujjrih/lukovofelerukepikakuziv.pdfIn PDF document text
    • https://nisewoji.weebly.com/uploads/1/3/4/2/134266574/d8e4d063f6.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4455894/normal_5ff41934ecd67.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466172/normal_5fd77f14f34bf.pdfIn PDF document text
    • https://cdn.sqhk.co/porosobof/coghgie/dutawe.pdfIn PDF document text
    • https://taxurazuzar.weebly.com/uploads/1/3/4/0/134042721/lidegaviverepaxop.pdfIn PDF document text
    • https://cdn.sqhk.co/muribirigim/jEetxhg/pizza_chef_quechee_mini_golf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450415/normal_5fd32b570e5f8.pdfIn PDF document text
    • https://pokumowudo.weebly.com/uploads/1/3/0/7/130740164/8339831.pdfIn PDF document text
    • https://tizezesi.weebly.com/uploads/1/3/4/0/134041120/fulifedubij.pdfIn PDF document text
    • https://dunelakanova.weebly.com/uploads/1/3/1/4/131410870/bedemifiximedanagax.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/b1b0cdad-9bd9-4645-83f2-6a9ab1226e9d/michael_talbot_the_holographic_universe_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4fa29080-de48-4917-877d-286fef91d600/40344896956.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/81fc401d-a2a0-445a-a07f-6639e8d07181/mercury_9.9_4_stroke_carburetor_diagram.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7b93c0d3-6ed2-4cd0-a91e-355e940b532f/cuantos_metros_cubicos_tiene_un_decimetro_cubico.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_off0000eb24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB24 5900 bytes
SHA-256: 73fb964e245fbc1acfb3db26ca8d93b081ddb16fff61c15e6bb8c7303610bb53
font_01_sfnt_off0000ff1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF1C 10736 bytes
SHA-256: 1f4c410c90e8fed74084f4eda35401d71743f28a07f14e07b7ecf49f37cdb1a4