Malicious PDF — malware analysis report

Static analysis result for SHA-256 387535f366e5c295…

MALICIOUS

PDF

84.9 KB Created: 2021-09-15 19:26:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 90b8dd8bb9f60aca20c37d7fba030481 SHA-1: 638fb8c332360348853af1dff8439bee391475d7 SHA-256: 387535f366e5c2950a1fd0017e57b17f31d3c5e151b7cd7588cbbda522533f55
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains numerous links pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the link farm and the PDF structure suggest it's intended to exploit user interaction to visit malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://ketchas.ru/uplcv?utm_term=nexus+7+running+slow PDF link annotation
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/0ipb7mhpqfo5snoiilugo2pifv/wanejajoxiwufaji.pdfIn PDF document text
    • https://expomediainc.com/upload/file/gawut.pdfIn PDF document text
    • http://rescue119.org/userfiles/file/31772213586.pdfIn PDF document text
    • http://namhungholdings.com/uploads/ckfinder/files/walosijumaburujaw.pdfIn PDF document text
    • https://mariapolis.es/ckfinder/userfiles/files/zokiju.pdfIn PDF document text
    • http://ohxto.com/uploaded_files/userfiles/files/96026521083.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/1de0013548ab4aadd7213999ceea11ee/jiwobimunegilerin.pdfIn PDF document text
    • http://vncdata.net/app/webroot/uploads/files/vuxovemeropebatikelari.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16135108bed1e8---70851351334.pdfIn PDF document text
    • https://tolgyesvolgy.hu/userfiles/file/bijivuvuruzavagor.pdfIn PDF document text
    • http://thetestmag.com/userfiles/files/51687612034.pdfIn PDF document text
    • https://31app.com/userfiles/file/54281114518.pdfIn PDF document text
    • http://avandcie-automation.com/ckfinder/userfiles/files/duvexinoz.pdfIn PDF document text
    • http://geasit.it/userfiles/files/44762414880.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/jumamegez.pdfIn PDF document text
    • http://domki-kopalino.pl/pliki/dobapijejinukavekebok.pdfIn PDF document text
    • https://rugerwafers.com/demo/ruger/beta/userfiles/files/dinimezi.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1614141bb1476c---repakobemiradut.pdfIn PDF document text
    • http://sarljarry.fr/userfiles/file/63695040282.pdfIn PDF document text
    • https://yourownadviser.com/ckfinder/userfiles/files/43449099086.pdfIn PDF document text
    • http://xutricolor.com/uploadfile/files/jimolakorowodibip.pdfIn PDF document text
    • https://ecowaytechnologies.com/ckfinder/userfiles/files/woxadezu.pdfIn PDF document text
    • http://1yunnan.com/ckfinder/userfiles/files/23241014940.pdfIn PDF document text
    • http://louisiana-arts.org.s150269.gridserver.com/siteuploads/editorimg/file/72580153414.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_off0000e8b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B8 10336 bytes
SHA-256: 096add60ec0baa9ba5ec8684c914c55e8899dde8ab2f453dda6e412a2bc0eca6
font_01_sfnt_off00010044.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10044 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011856.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11856 17608 bytes
SHA-256: d572edb627f1017919e8a0b4a95d21f2a2c99d565f944003076c91ad5de7f622