Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf9ab199a73cc64f…

MALICIOUS

PDF

145.0 KB Created: 2021-04-07 14:20:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: c3bdc8df9a172a761bc3ce6e07654624 SHA-1: f351dee3fe1b1597196317c7245e0211b11b827d SHA-256: cf9ab199a73cc64f0d2128d9c0741091f8a651e5a8027523421732b5bb916730
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by multiple heuristics and an ML classifier, indicating a phishing or malware distribution attempt. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm designed to redirect users to potentially malicious sites. The presence of 'wkhtmltopdf' in the metadata suggests it may have been generated programmatically for SEO spam or phishing purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://botokaw.ru/square?utm_term=sejarah+gamelan+melayu+pdf PDF link annotation
    • http://desekikimok.22web.org/wezigawotasafofazanewuz.pdfIn PDF document text
    • http://nufefabipiketod.22web.org/71228268816.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418590/normal_60695a82bafd7.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4475212/normal_5ff9de11e6800.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384050/normal_6048a968eeadd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447253/normal_604dcbecb4572.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417834/normal_60189f2f60d1d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4483873/normal_606aaa061e872.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://217ba8a6-026c-4a9e-b1ce-2eadff0a4a08.filesusr.com/ugd/3d7af5_682fbd7d7bce4724887c7acd26e40f13.pdf?index=trueIn PDF document text
    • https://8d67285a-e3c5-4820-bb1a-bb91ce1079a6.filesusr.com/ugd/d54300_0d2dfc55369148339b88be0e6b42c909.pdf?index=trueIn PDF document text
    • https://436240a4-ef10-404e-ad90-c5cab949c7af.filesusr.com/ugd/3fb742_f504f2f4635346ebac543d2159ada0f5.pdf?index=trueIn PDF document text
    • http://fonobufusig.rf.gd/89750106706.pdfIn PDF document text
    • https://s3.amazonaws.com/nawuvud/3_types_of_leadership_styles.pdfIn PDF document text
    • https://s3.amazonaws.com/lerezazo/90964232595.pdfIn PDF document text
    • https://31e64076-56b3-4e53-9780-179364fbad2f.filesusr.com/ugd/d8d3cb_e6b8d70b270b428abc048e18fc2d93ae.pdf?index=trueIn PDF document text
    • https://fac30f9c-1bc3-4ff6-ac40-7ced1d2a170b.filesusr.com/ugd/3b7182_fd03f38b1a004fdabd28d2c7b0098c23.pdf?index=trueIn PDF document text
    • https://8c17aa34-c454-4d6c-a218-8929c845e329.filesusr.com/ugd/808cd0_6e09699baeda40369fe65dd2754d971e.pdf?index=trueIn PDF document text
    • http://veduredetud.epizy.com/ansi_device_codes.pdfIn PDF document text
    • https://s3.amazonaws.com/lurutopobi/86250775222.pdfIn PDF document text
    • https://5d9de69b-f80b-44d6-9c2d-9027806fef0b.filesusr.com/ugd/e26ad2_f00f17df36464b8a85cfaf3bc5265092.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_off0001f973.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1F973 5556 bytes
SHA-256: f1b825ec5f71a3dec2d0df6289124d93ceeba1fa04db4ff874f29a4edf3ded36
font_01_sfnt_off00020c3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x20C3E 12724 bytes
SHA-256: 7b086633911488827ecf2f9f0404003769e6c0669d78ad1898fbd9bf30db0d32