Malicious PDF — malware analysis report

Static analysis result for SHA-256 0bf1f66e2137a6c2…

MALICIOUS

PDF

83.4 KB Created: 2021-09-11 03:19:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: d3cfd0faa3af781ce2e43634df9c4dd1 SHA-1: 428f5f8c8b747a882b9b36becd489507a5fcb460 SHA-256: 0bf1f66e2137a6c2975e325930aa852584f35d890f5dbd789b275d1745d032f8
126 Risk Score

Malware Insights

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

The PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to PDF files hosted on potentially disposable domains, suggesting a link farm or redirection scheme. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true destination or inflate search engine rankings. While no scripts were explicitly extracted, the nature of the heuristics and the embedded URLs strongly suggest an attempt to direct users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://mopi.eu/ckfinder/userfiles/files/63376498018.pdf In PDF document text
    • https://chupwo.com/editor_upload/file/favodakogog.pdfIn PDF document text
    • https://bomando.bomsolar.com/uploadfiles/files/varikarure.pdfIn PDF document text
    • http://medrea.ru/upload/files/45325229817.pdfIn PDF document text
    • http://fishtech.org/uploads/userfiles/file/file/99354965324.pdfIn PDF document text
    • http://aqbnb.com/uploadfile/file/denudesejaxagexunum.pdfIn PDF document text
    • https://turismopontevedra.com/ckfinder/userfiles/files/kujozujoduriwi.pdfIn PDF document text
    • http://basumati.com/app/webroot/ckfinder/userfiles/files/20237421122.pdfIn PDF document text
    • http://sweethomedelivery.com/ckeditor/ckfinder/core/connector/php/uploads/files/99263258554.pdfIn PDF document text
    • https://solelane.com/ckfinder/userfiles/files/13198988166.pdfIn PDF document text
    • https://multimetrics.com/ckfinder/userfiles/files/towezizuxodarabaj.pdfIn PDF document text
    • https://rajatotogroup3.com/contents/files/medodalolutodigoz.pdfIn PDF document text
    • http://attep.com/home/sandbox/domains/heekee.com.hk/public_html/ckfinder/userfiles/files/89124227334.pdfIn PDF document text
    • https://topclassgardening.nl/images/file/92707149757.pdfIn PDF document text
    • http://yhbinternational.com/userfiles/file/31523796267.pdfIn PDF document text
    • http://lnimeina.it/userfiles/files/46389450233.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1613543d30ab04---67248830262.pdfIn PDF document text
    • https://fontan-montag.ru/img/upload/bizikir.pdfIn PDF document text
    • http://jandenzobv.com/image_uploads/file/duguratokimuf.pdfIn PDF document text
    • https://igruppe.no/ckfinder/userfiles/files/webemezosupukeliluxem.pdfIn PDF document text
    • http://signauction.net/userfiles/file/10466360426.pdfIn PDF document text
    • http://roomyab.ir/basefile/roomyabir/files/92796926351.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=easy+for+apkPDF 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_off0000e4d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4D9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fceb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCEB 17560 bytes
SHA-256: 726b37362a312e67dcf1a51d7273fe28b71bd17e60d2de7823b213abfb9e3ffa
font_02_sfnt_off00012a3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A3B 10068 bytes
SHA-256: e79ce525fd1557309dd3167cb5a409324fa4821692a3910ae7b353e44b445226