Malicious PDF — malware analysis report

Static analysis result for SHA-256 8690f9405c2c9e3a…

MALICIOUS

PDF

74.4 KB Created: 2021-09-23 00:26:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b35deb8770faaede742e65f16e3f12a3 SHA-1: 911bf6b09130f141a115dbb8d205fbadaa02012a SHA-256: 8690f9405c2c9e3ab8eb4efa3ffa98dfe8e0f6f14c69c5a8b5457806ebf697a7
126 Risk Score

Malware Insights

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

The sample was detected as a malicious PDF by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to various domains, suggesting it functions as a link farm or redirection mechanism to external malicious sites. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true destination or distribute content across many domains. While no scripts were explicitly extracted, the PDF structure and embedded URLs strongly suggest it is used to direct users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://jasz-pap.hu/UserFiles/file/xegat.pdf In PDF document text
    • http://avtokit116.ru/!upload/files/33925556928.pdfIn PDF document text
    • http://krakowska98.com/zdjecia/fck/file/lejesixe.pdfIn PDF document text
    • http://erictex.com/ufiles/files/ponokozafunanabigemob.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16139f6d6357f2---velipukenut.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/94339160992.pdfIn PDF document text
    • http://esipro.fr/userfiles/file/53700857128.pdfIn PDF document text
    • https://52fantasies.com/home/holly/public_html/ckfinder/userfiles/files/bibunovux.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a5d5086356---jejakomagejibi.pdfIn PDF document text
    • http://miryangpension.com/FileData/ckfinder/files/20210919_470735D23ED7BDED.pdfIn PDF document text
    • https://alajuusa.ee/media/contents/file/53610482981.pdfIn PDF document text
    • http://nexxosrealty.com/userfiles/files/40655171338.pdfIn PDF document text
    • https://zniczekowalczyk.com/user_images/file/9306528889.pdfIn PDF document text
    • http://dfwarbitrator.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/49524192717.pdfIn PDF document text
    • http://mn-print.ru/ckfinder/userfiles/files/lasaziz.pdfIn PDF document text
    • http://pobierzplik.pl/uploads/files/8964449153.pdfIn PDF document text
    • https://saint-florentin.charcutier-traiteur.fr/ckfinder/userfiles/files/85205630031.pdfIn PDF document text
    • http://kirsanov-maslo.ru/uploads/vewelemivalapafakiwipe.pdfIn PDF document text
    • http://theemasternetworker.com/ckfinder/userfiles/files/20930556295.pdfIn PDF document text
    • https://bisnismedsos.com/userfiles/file/gubupobilomojorapuvoso.pdfIn PDF document text
    • http://krishikhabar.net/assets/ckfinder/core/connector/php/uploads/files/68487730315.pdfIn PDF document text
    • https://rowadalbyt.com/userfiles/files/naroxozugun.pdfIn PDF document text
    • https://toptenstudy.com/upload/files/BodyFile__61447B5D64BFF.pdfIn PDF document text
    • http://gearonlaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/14156496205.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=heart+of+darkness+ps1+romPDF 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_off0000bf5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF5B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d772.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD772 10656 bytes
SHA-256: e1401da7efd945bfbe28fde1aa26a82ebebd0e661c4a42f95eb46bafa4c242f8
font_02_sfnt_off0000efdc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFDC 16944 bytes
SHA-256: 753a742449b9a0baa1e2760304b148b6dc1e6779c45176cea025d1d0786c7b37