Malicious PDF — malware analysis report

Static analysis result for SHA-256 da436f2ec037839b…

MALICIOUS

PDF

145.4 KB Created: 2021-09-04 02:26:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: f65d0379f0da1eba4c06bb7c2d886b13 SHA-1: da2214438fbc42fe442f7394e5135444f4ae9488 SHA-256: da436f2ec037839b235cfe74dad03baac4ba86e1414e5f99cb4fc2e691ca2240
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to potentially harmful sites. The document body is heavily obfuscated and appears to be metadata rather than user-readable content, further supporting a non-legitimate purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://pjkconstruction.ca/images/file/jafigunogosavup.pdf In PDF document text
    • http://radio-salsa.com/php/rs/filesupload/file/12709591271.pdfIn PDF document text
    • http://vet-arrighicolangelicristilli.eu/userfiles/files/17838914858.pdfIn PDF document text
    • https://verlauf-ekb.ru/admin/ckfinder/userfiles/files/wuned.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ff2b27cd53---76538318766.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a213b3aaf58---lawakovidumebikatoso.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/978a30566fcb09a18f7a5f14d899fec2/fekedometejomesub.pdfIn PDF document text
    • http://newcastlehigh1967-50threunion.com/clients/43248/File/zufatowugof.pdfIn PDF document text
    • http://spec-so.ru/sites/default/files/file/bosevakotivoduxedexonef.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/vhqs3b2vdc0bf3tiu3dnud9lk2/36179960574.pdfIn PDF document text
    • https://taichielite.com/louis/taichi/ckfinder/userfiles/files/23034140690.pdfIn PDF document text
    • https://shayangroup.net/wp-content/plugins/super-forms/uploads/php/files/9ee804bd9b1c4aacc544804ee23738f3/kagon.pdfIn PDF document text
    • http://spadhotel.com/basefile/spadhotelcom/files/75898493282.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160a83dc3e2512---97252738546.pdfIn PDF document text
    • https://maximatrimony.com/ckfinder/userfiles/files/80145230481.pdfIn PDF document text
    • http://zhfangyuan.com/uploadfiles/files/giziwegonapavikegurixoga.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9b38498dc9---rovaxexufawogifatu.pdfIn PDF document text
    • http://xn--h1agcmh.com/ckfinder/userfiles/files/59184911092.pdfIn PDF document text
    • https://pfollowers.com/ci/userfiles/files/28991462737.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073fe284bd9e---10925022355.pdfIn PDF document text
    • http://morecoredesign.com/images/imageUps/files/jebapizegujapijojesogava.pdfIn PDF document text
    • http://menloathertonhigh1980.com/clients/6/6f/6f83464fe0b13873896cace574d4baa5/File/18040571255.pdfIn PDF document text
    • http://mastera-mix.ru/ckfinder/userfiles/files/lakamomafataluwu.pdfIn PDF document text
    • http://huiking.cn/uploads/file/271730279353.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609a71e0a5cd7---wuxevipogu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=metodos+de+programacion+no+lineal+pdfPDF 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_off0001cab9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1CAB9 10956 bytes
SHA-256: ca91d95b4447ea77b0f8849cbf671a4bb838a9714717cbd4fe9858d9f50fa9cb
font_01_sfnt_off0001e3ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1E3ED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001fbff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1FBFF 22768 bytes
SHA-256: ee5e152e433830a1ff7609b37ec43cff8a95635677c0316cfb212dfcb79b432a