Malicious PDF — malware analysis report

Static analysis result for SHA-256 28ac9f6f0f36f9df…

MALICIOUS

PDF

100.0 KB Created: 2021-03-20 22:45:54 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: b5a2f9fa123b80d3c91d982f09902ea2 SHA-1: b70eee8cd19abd939125f1ed83e9d45aafc4c0ab SHA-256: 28ac9f6f0f36f9dfa0861d26c170ed06b8041eb1b88e96d6027b9121f7138d91
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to other PDF documents hosted on various domains. This behavior is indicative of a link farm, often used for SEO manipulation or to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution via these linked documents.

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://ponafet.ru/wix?keyword=the+rough+guide+to+climate+change+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4481830/normal_6028622739b10.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393364/normal_6031ff6069e76.pdfIn PDF document text
    • https://cdn.sqhk.co/ziloteduxemo/MgeNFZZ/10012659384.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4386618/normal_5ff7ef4059a6e.pdfIn PDF document text
    • https://cdn.sqhk.co/sopiloroda/4ggjaih/8208196665.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413862/normal_5fe80fe31dd7c.pdfIn PDF document text
    • https://cdn.sqhk.co/vozevadijut/fn6hiKW/duvafadu.pdfIn PDF document text
    • https://cdn.sqhk.co/rogapakaler/giggdhi/5152613245.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465123/normal_6047ebfbaf00a.pdfIn PDF document text
    • http://purejup.iblogger.org/cucumber_reporting_dependency_maven.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4502817/normal_5fccb1e115cc7.pdfIn PDF document text
    • https://cdn.sqhk.co/famuxina/c2jaBXL/texas_uncontested_divorce.pdfIn PDF document text
    • https://cdn.sqhk.co/wekaradukuve/sQjbiic/wimivejapifokevafelewode.pdfIn PDF document text
    • https://cdn.sqhk.co/wugunifikezu/haoPQgi/22695166062.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405185/normal_601830fb22fbc.pdfIn PDF document text
    • https://cdn.sqhk.co/rifebonapesi/hc1Fjag/viking_voyager_ferry.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452373/normal_604d1e9d8b89f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404965/normal_6010ddca1572a.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://segipiked.epizy.com/mukosemun.pdfIn PDF document text
    • https://89511c73-251b-4bee-a1a5-5f4bd4863124.filesusr.com/ugd/f24cb8_1e02143dfc974d9cbb2786f2e0b94780.pdf?index=trueIn PDF document text
    • https://ebc1add8-0b9d-418e-9e4a-1e287827e933.filesusr.com/ugd/ab63e3_24c203b74bc44816a35bcc583eb5065b.pdf?index=trueIn PDF document text
    • http://boligasenupe.rf.gd/terekubosifowipop.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_off0001489d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1489D 5340 bytes
SHA-256: 89f5a10a78273bc0a3c4a5af45ceec954ad1ba6e729be5136ffc1274bf2b498b
font_01_sfnt_off00015aa0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15AA0 11348 bytes
SHA-256: bf045749ed3242242fbed31a4b2c9f0f4766238f4183113b362076e4f9b50168