Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f79069dd3c9aab3…

MALICIOUS

PDF

87.4 KB Created: 2021-09-15 18:34:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: f7f2eb604d9078145429450d9689a9aa SHA-1: 030dd481ed974ac70453b3045df31b75639e0d22 SHA-256: 4f79069dd3c9aab3e36cffb5beb180010d10576021201563dbb135aa4d16327d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to external domains, and a high-confidence ML classifier flagged it as malicious. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a large number of links on disposable hosting, suggesting a phishing or spam campaign. While no scripts were explicitly extracted, the nature of the PDF and its embedded links strongly suggest it's used as a lure to direct users to malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 5

  • 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 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://wastran.ru/uplcv?utm_term=world%27s+7th+largest+country PDF link annotation
    • http://hyundaidongdo3s.com/images/files/69565428356.pdfIn PDF document text
    • https://oilbasaro.com/web/images/ckfinder/files/20210905041218.pdfIn PDF document text
    • http://asja-doll.ru/userfiles/file/fuwebovexobirazubefi.pdfIn PDF document text
    • http://aedelsur.com/contenido/files/lipafufagomimixes.pdfIn PDF document text
    • https://funcarele.com/ckfinder/userfiles/files/ledajusop.pdfIn PDF document text
    • http://nawoo.net/userData/board/file/62296374051.pdfIn PDF document text
    • https://doina.md/fckeditorfiles/file/76567313153.pdfIn PDF document text
    • http://www.gitialiganjlko.org/ckfinder/userfiles/files/1295047724.pdfIn PDF document text
    • https://marblobaths.ph/app/webroot/img/files/wogezumupuvulaxatifebe.pdfIn PDF document text
    • http://burelomdo.com/ckfinder/userfiles/files/ledixatowafajisu.pdfIn PDF document text
    • https://dijitalsanat.link/upload/files/wereti.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137583525a7f---41163566503.pdfIn PDF document text
    • http://webinaris.org/ckfinder/userfiles/publics/files/50511796065.pdfIn PDF document text
    • https://maviet.vn/upload/files/48546882344.pdfIn PDF document text
    • http://bjdfszwy.com/filespath/files/20210914141214.pdfIn PDF document text
    • https://bodykneadstherapy.com.au/ckfinder/userfiles/files/43107261798.pdfIn PDF document text
    • https://blagoustroystvo24.ru/ckfinder/userfiles/files/67120868654.pdfIn PDF document text
    • http://pixel-pro.ru/upload/file/fadosufijepepelowoxi.pdfIn PDF document text
    • https://apsco.ly/userfiles/files/kawifolesivafisapasak.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f5793bf733---xofekegezuwilonerom.pdfIn PDF document text
    • http://dwallacelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/50777340933.pdfIn PDF document text
    • http://bargiel.com.pl/ckfinder/userfiles/files/pudigew.pdfIn PDF document text
    • https://cebubigsellers.com/userfiles/file/dapiguvizesikovatipalemi.pdfIn PDF document text
    • http://maiodi.com/userfiles/files/57105482547.pdfIn 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://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_off0000f04a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF04A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010861.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10861 10848 bytes
SHA-256: 449a8a4f5253ae1c144873a7e0fafdc4d3e64981ecadbfba51a141142e52edcf
font_02_sfnt_off00012154.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12154 18148 bytes
SHA-256: a8a35984667c5f0fdfd9b45364541814dcc5922394464609d874ed54b710d397