Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2b7c576b0ab41cf…

MALICIOUS

PDF

73.8 KB Created: 2021-03-21 12:19:22 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-28
MD5: 39d646c6b4eb407dd7e93813550c98d9 SHA-1: 985abaed37863e322dc820bae4e5acdb47043b6e SHA-256: b2b7c576b0ab41cf9d9e78fe88ece3995745bf16ade92c0095538636ab0fa7cb
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links pointing to various domains, many of which appear to be disposable or part of a link farm. The ML classifier and ClamAV detection strongly indicate maliciousness. The primary attack pattern involves directing users to a network of SEO-optimized PDF documents, likely to facilitate phishing or distribute further malware.

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://maypoin.ru/award?keyword=functional+english+grammar+and+composition+solutions+class+9+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4486197/normal_5fd9e7576a54e.pdfIn PDF document text
    • https://marabobufazezi.weebly.com/uploads/1/3/5/9/135992859/acbb796.pdfIn PDF document text
    • http://newoxoxi.mywebcommunity.org/modelo_de_contrato_de_arriendo_departamento_amoblado.pdfIn PDF document text
    • http://zugasanuko.getenjoyment.net/vomomasegujuz.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381541/normal_6029563007d1e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444884/normal_6034df525e224.pdfIn PDF document text
    • https://xapebetilozeze.weebly.com/uploads/1/3/0/8/130873864/wepawoxux-pojokorebuvibur-gojawesowibasa.pdfIn PDF document text
    • https://zixaxufomomofir.weebly.com/uploads/1/3/0/7/130738537/wiwosirev.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391000/normal_600dc8ca906c5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368229/normal_604a90a01bfc3.pdfIn PDF document text
    • https://lorivomewojesab.weebly.com/uploads/1/3/0/8/130813497/cf156666f01d4.pdfIn PDF document text
    • https://fomodaduvi.weebly.com/uploads/1/3/4/7/134700625/d510c7e9e91824.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4478928/normal_5fe3f6252bc43.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4368972/normal_5fc63a1cda9fc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4488323/normal_6015ffc4590f1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://6cda4dd4-8aac-43e7-8003-7c0eea9f7907.filesusr.com/ugd/34e26e_3ab68258e6344ff78fe4386e17c1e39b.pdf?index=trueIn PDF document text
    • http://xowobovu.myartsonline.com/what_is_your_zip_code_in_philippines.pdfIn PDF document text
    • https://8ed62699-7d02-4439-b935-4286882ef7d4.filesusr.com/ugd/229b11_2d8451bd66d14735b83b665b98893374.pdf?index=trueIn PDF document text
    • https://9c789f27-b70c-4c9d-9e83-211ee8f99b38.filesusr.com/ugd/bdeb4c_828f583f972744dfb1b8151875e116aa.pdf?index=trueIn PDF document text
    • https://9e730ba1-499c-413e-9a09-8a81f8121270.filesusr.com/ugd/0a0016_c7ce5a8183054b2fa0ac7309aedb6584.pdf?index=trueIn PDF document text
    • https://ebd157e6-94c3-4ff5-b3ab-516f87acbde6.filesusr.com/ugd/e87473_fe12c1cdd6dc405ab22e28419ce5fd04.pdf?index=trueIn 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_off0000df72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF72 5680 bytes
SHA-256: 6bb7e170b68c601a90b72e24552dbc9915f0ec24f62cb13e7b79c4b92a56ab0e
font_01_sfnt_off0000f29c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF29C 11488 bytes
SHA-256: d97ea9b86456cf9f091ac0820064402ecc8c362a2edd8d0d7311e3606bca68c5