Malicious PDF — malware analysis report

Static analysis result for SHA-256 7833e5b668097e23…

MALICIOUS

PDF

88.1 KB Created: 2021-09-10 05:43:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 990f12755ba5787028f967f111b58ab7 SHA-1: dd1ab0fb355f8f9fa04671de719f5fab0758a5aa SHA-256: 7833e5b668097e234a3963ccd6aa9a5ac793bd03e57f3e25ac3e9684322d7fb0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a non-clustered link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131221023cab---fagunewovuta.pdf In PDF document text
    • http://kenshopvn.com/uploads/files/9097304037.pdfIn PDF document text
    • https://serwisnawigacji.pl/userfiles/file/22321332753.pdfIn PDF document text
    • https://www.auto-ecole-rive-droite.fr/ckfinder/userfiles/files/19832066324.pdfIn PDF document text
    • http://nikkenj.com/userfiles/file/daxarijedotuvaguve.pdfIn PDF document text
    • https://www.andreivieru.com/ckfinder/userfiles/files/93118708570.pdfIn PDF document text
    • http://avision-italia.com/userfiles/files/jajokipidotixo.pdfIn PDF document text
    • http://alhambra.kopanramen.com/uploads/files/56077926933.pdfIn PDF document text
    • https://cuacuonbentre.com/upload/files/tuzarexegijelameneza.pdfIn PDF document text
    • http://suliaok.com/v15/Upload/file/2021910021374564.pdfIn PDF document text
    • http://alicekhenrylawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xamutuwavupur.pdfIn PDF document text
    • http://thaicockstar.com/ckfinder/userfiles/files/53355160614.pdfIn PDF document text
    • http://altronic.pl/!mag2011/userfiles/file/moxowupuludidigurapozegiz.pdfIn PDF document text
    • https://egyiksem.hu/uploads/file/zagevagusikeru.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135b5e6765a1---pufop.pdfIn PDF document text
    • https://archielectronics.com/userfiles/files/20212445289.pdfIn PDF document text
    • http://cutskytools.com/d/files/37918786619.pdfIn PDF document text
    • http://iberryhomemade.com/userfiles/files/wakip.pdfIn PDF document text
    • http://thcsnguyenvanhuyen.hoaiduc.edu.vn/ckfinder/userfiles/files/soxesesinugevag.pdfIn PDF document text
    • https://libertyrealestate.in/ckfinder/userfiles/files/nubanuxowinafoka.pdfIn PDF document text
    • http://xaydunghoangthanh.com/img_duhoc/files/sofokaf.pdfIn PDF document text
    • http://acsalma.hu/userfiles/files/tajawokedizanapenupeb.pdfIn PDF document text
    • http://winteringlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zazisupuromavimavazisulol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=descargar+canciones+androidPDF 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_off0000f16c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF16C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010983.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10983 10400 bytes
SHA-256: b164a484ac56b2150a4a20f3f989e74ee37d176082712272841ea44f62751557
font_02_sfnt_off000120f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120F6 19816 bytes
SHA-256: 74f72a6a989185cde65030f02fdd7f9dc7bd279cf85997209301c19463f96ba8