Malicious PDF — malware analysis report

Static analysis result for SHA-256 492aec0c2e0fea07…

MALICIOUS

PDF

124.4 KB Created: 2021-09-17 15:55:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e1237c1a643f9b113cc198ac4a26b764 SHA-1: 23e0c4d9881e26ca87371ce1c73e59601f2fbab7 SHA-256: 492aec0c2e0fea07599313dac332e3f269cce117d596e2190c0c2c6d6417f138
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many pointing to disposable domains, suggesting a link farm or phishing lure. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically indicates a non-clustered link farm on disposable hosting, reinforcing the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • 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 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://24emk.ru/ckfinder/userfiles/files/sudasazukeponedu.pdf In PDF document text
    • http://sin-hua.org/userfiles/jonagesexidapekoza.pdfIn PDF document text
    • http://akcompany.vn/uploads/userfiles/file/60828965200.pdfIn PDF document text
    • https://szamitogep-szerviz-javitas.hu/ckfinder/userfiles/files/16027955011.pdfIn PDF document text
    • http://verzorgingsindex.nl/images/uploads/18772849196.pdfIn PDF document text
    • https://prestinieurope.ch/userfiles/files/nuwivovokajukozurepi.pdfIn PDF document text
    • http://iberryhomemade.com/userfiles/files/68838565267.pdfIn PDF document text
    • https://pesonabali.dswip.com/ci/userfiles/files/dapuwup.pdfIn PDF document text
    • https://www.colline-eternelle.com/ckfinder/userfiles/files/42646417713.pdfIn PDF document text
    • http://lawfirm.vn/MINH/user_files/file/gezod.pdfIn PDF document text
    • http://yavuzselimvakfi.org/resimler/site/files/22100909708.pdfIn PDF document text
    • http://vuoncotichdep.com/upload/files/37087310162.pdfIn PDF document text
    • https://holcom-wd.holcom.vn/webroot/img/files/faxepafugid.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/161333a4413d7c---lapodakeviziruwatuked.pdfIn PDF document text
    • http://decoworld.in/dayafter/uploadimages/newsimages/file/pomewuxenu.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/161376e9248b02---7850015297.pdfIn PDF document text
    • http://dija.lv/public/userfiles/file/1938856194.pdfIn PDF document text
    • https://ribaczpeter.hu/files/file/6260306199.pdfIn PDF document text
    • http://biomehl.com/images/content/files/52660080275.pdfIn PDF document text
    • https://edex.co/userfiles/files/282992852.pdfIn PDF document text
    • http://ride.hu/images/uploads/files/30965118488.pdfIn PDF document text
    • http://harmonie-avion.fr/actualite/files/40048526878.pdfIn PDF document text
    • https://nieruchomosciprzetargi.pl/files/file/92687400591.pdfIn PDF document text
    • http://kipia-nn.ru/userfiles/file/fadoginijupovowebeso.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=the+ultimate+medical+mnemonic+comic+book+pdf+free+downloadPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00017dfd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17DFD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00019614.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19614 11096 bytes
SHA-256: d2a3de8c61ca8af0e338015160768426c0cf35c838445779ac9ac92b0de2ddbd
font_02_sfnt_off0001af8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1AF8D 20268 bytes
SHA-256: f22c2f9a8b04623ee986bdac9cbadb37ba0247a24ad06b114c11ec19d62dc7e9