Malicious PDF — malware analysis report

Static analysis result for SHA-256 af7ea46194aaff7f…

MALICIOUS

PDF

74.4 KB Created: 2021-09-19 20:21:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 22f5b5a7d3c94f3738f31e8abe2865b2 SHA-1: 9e7725c480120df4f7534e65aac84430b905eff5 SHA-256: af7ea46194aaff7f5ddc18747bd4d105375bf2bceb056fd3b72a52a8b7e80c8c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV and an ML classifier as malicious. It contains numerous embedded URLs, many of which point to suspicious domains and appear to form a link farm, suggesting a potential SEO manipulation or content distribution scheme. The `PDF_SEO_DISPOSABLE_LINK_FARM` heuristic further supports this, indicating a non-clustered link farm on disposable hosting. No scripts were extracted, but the presence of external URIs and the overall structure suggest a phishing or malicious content delivery attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9901

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 http://cserepakciok.hu/xdata/file/94027830292.pdf In PDF document text
    • https://vanrun-it.nl/userfiles/files/zaginubuvofowameledasapiz.pdfIn PDF document text
    • https://clinicaabrahaoosta.com.br/ckfinder/userfiles/files/98887099633.pdfIn PDF document text
    • https://www.cosanuesa.com/componentes/editor/ckfinder/userfiles/files/77551681623.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1613ebb8fcca1f---riwuwalumamuwovufa.pdfIn PDF document text
    • http://grgct.com/ckfinder/userfiles/files/filiparam.pdfIn PDF document text
    • https://i-intelli.com/ckfinder/userfiles/files/1448863616.pdfIn PDF document text
    • http://geologocarmignani.com/userfiles/files/zopofonabemef.pdfIn PDF document text
    • https://kimansion.com/uploads/file/97918791502.pdfIn PDF document text
    • http://powercleanperu.com/cms_powerclean_2015/sgi_userfiles/userfiles/files/9092067699.pdfIn PDF document text
    • https://rlmahtani.com/userfiles/files/84919069395.pdfIn PDF document text
    • https://ardiinerkh.mn/uploads/userfiles/files/zafigixejugafipetuwevu.pdfIn PDF document text
    • http://jngf.cn/files/file/6474704592.pdfIn PDF document text
    • https://resttour.com/images/userfiles/files/kixokogejak.pdfIn PDF document text
    • http://sewakendragroup.com/userfiles/file/zasovonugowufuzeb.pdfIn PDF document text
    • https://ooo-kenk.ru/userfiles/file/nafaxibewexudirubebut.pdfIn PDF document text
    • http://pyhunlian.com/uploadfile/file/63850257233.pdfIn PDF document text
    • http://krakow4you.pl/krakow/files/996500024.pdfIn PDF document text
    • https://carparts-fixture.com/file/file/27256289881.pdfIn PDF document text
    • https://www.servicespace.org/inc/ckfinder/userfiles/files/735610174.pdfIn PDF document text
    • http://misosmile.com/upload/editor/files/kadurisapopisetaxikaxi.pdfIn PDF document text
    • http://bioaec.com/userfiles/files/32955414327.pdfIn PDF document text
    • http://futurepoolandspa.com/ckfinder/userfiles/files/54223984300.pdfIn PDF document text
    • https://holycrosshealthcare.com/userfiles/files/53162449605.pdfIn PDF document text
    • http://winterwonderlandzundert.nl/uploadimages/files/58170898846.pdfIn PDF document text
    • http://xn----9sbbnbtte4cyg.xn--p1ai/ckfinder/userfiles/files/gimikizozururatutazudig.pdfIn PDF document text
    • https://evpersoneli.net/ev-personeli/file/6537596026.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=gujarati+alphabet+book+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_off0000be17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE17 16980 bytes
SHA-256: 54e293e0ee722182f5e0bb0b612e6dd72f31a3027e525a51f871d90fe735af35
font_01_sfnt_off0000ea63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA63 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001027a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1027A 10824 bytes
SHA-256: 28213aa2133640ebdf6d223ecb49817cf69cf4f2d141cf93ac4968d19eefdbe6