Malicious PDF — malware analysis report

Static analysis result for SHA-256 425fbe5d93129f5e…

MALICIOUS

PDF

83.0 KB Created: 2021-10-05 13:47:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: ea7490d1ee2fd16254e35263ef18eeff SHA-1: 20ab718415117bf15332fcfdcbb208f06de59cf8 SHA-256: 425fbe5d93129f5e3eb885208e7d37b8535efa4733a4fbb033f96da0efea8b7f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with one heuristic specifically identifying it as a link farm on disposable hosting. ClamAV and ML classifiers also flagged the file as malicious. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an intent to redirect users to potentially harmful content, aligning with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://laborke.ru/uplcv?utm_term=linear+pair+definition+geometry PDF link annotation
    • http://blueyee.com/upload/file/2222214213.pdfIn PDF document text
    • http://xn----7sbqwxdbhblh2h.xn--p1ai/data/file/gadifuxibewu.pdfIn PDF document text
    • http://pdww.ru/ckfinder/userfiles/files/sidutubasosajedubefozi.pdfIn PDF document text
    • http://cga82.com/admin/File/gowejibulodesuwokupu.pdfIn PDF document text
    • https://angkorphotographyguide.com/userfiles/file/labukojewitofasake.pdfIn PDF document text
    • https://askisan.com/upload/ckfinder/files/supovokugisexisasub.pdfIn PDF document text
    • http://gustosandvic.com/ckfinder/userfiles/files/72324431854.pdfIn PDF document text
    • https://spheresignal.com/app/webroot/userfiles/files/14585564939.pdfIn PDF document text
    • https://blokhol.com/upload/files/woxepelimijejobofakose.pdfIn PDF document text
    • http://www.angels-rest.es/ckfinder/userfiles/files/digabidubi.pdfIn PDF document text
    • http://bociany.sk/media/file/bifutisezepuvijufim.pdfIn PDF document text
    • http://jgbt.us/pds/userfiles/files/67555069038.pdfIn PDF document text
    • http://aytekinpolatel.com/image/files/71917664902.pdfIn PDF document text
    • http://daeryuhealthcare.com/ckupload/files/sojubuwos.pdfIn PDF document text
    • https://cometsecurity.in/admin/userfiles/file/xewudekizozaxidipakis.pdfIn PDF document text
    • http://quangcongluc.com/upload/files/44079865681.pdfIn PDF document text
    • http://www.lauricedale.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161500c3d1a43b---pirigexavirafolave.pdfIn PDF document text
    • http://fzsvybbs.at/userfiles/file/soporedesoganovumizij.pdfIn PDF document text
    • http://artechq8.com/beta/uploads/files/32893119679.pdfIn PDF document text
    • https://zoldlepes.hu/userfiles/file/97899853240.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/didotewezedop.pdfIn PDF document text
    • https://zohopin.com/calisma2/files/uploads/68350730874.pdfIn PDF document text
    • http://foodchemsino.com/d/files/dozezimonekakesezow.pdfIn PDF document text
    • http://wo-kop.pl/userfiles/file/gidenufiw.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/202ed36e0bc01c8a7c560a0c1f5c239f/zibuxaxavawopiribadafiba.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_off0000d979.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD979 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f190.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF190 10700 bytes
SHA-256: b59d3a57e38edef3381aa1bffa22b731fcd2671656a056a4c4452b9e4a55ad5c
font_02_sfnt_off000109db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109DB 20208 bytes
SHA-256: 0c5e166d0eedb5784962babfbda32a90bacc3178f6c3c6696e1eacca76e49fa7