Malicious PDF — malware analysis report

Static analysis result for SHA-256 03755f70140382aa…

MALICIOUS

PDF

74.9 KB Created: 2021-09-19 14:14:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e9991ff793057c49d7890ed795f216ab SHA-1: 2f8db37cdb44c6291c87bf00902c851208b621f5 SHA-256: 03755f70140382aa4476dd83d1d631684f710328d967e67cbdfc8ad10414d33f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The embedded URLs and the heuristic detecting a link farm on disposable hosting suggest the document is designed to redirect users to potentially harmful websites, possibly for phishing or malware distribution. The document body, though heavily obfuscated, contains metadata indicating it was generated by wkhtmltopdf, a tool sometimes used to create malicious PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 https://palezieux.com/ckfinder/userfiles/files/mesukusaxoluseti.pdf In PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/a8vagh0a3ibsu907o7lno752h4/kivijujumiw.pdfIn PDF document text
    • http://chithanhplastics.com/uploads/userfiles/file/ruduremubidigisebe.pdfIn PDF document text
    • https://odontologosmalca.com/images/userfiles/file/nusonefefamobe.pdfIn PDF document text
    • http://smarttechsolutionukltd.com/uploaded_files/userfiles/files/mexama.pdfIn PDF document text
    • http://pecsimutargygaleria.hu/files/file/67825069406.pdfIn PDF document text
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/nidozapobazix.pdfIn PDF document text
    • https://tattica.byespresso.com/app/webroot/files/upload/files/18130623994.pdfIn PDF document text
    • https://postelezmasivu-liberec.cz/ckfinder/userfiles/files/52868674359.pdfIn PDF document text
    • http://emotionpicturesfestival.gr/userfiles/file/jopijasibuzemisuda.pdfIn PDF document text
    • http://morpheus-architects.com/file_media/file_image/file/47030923107.pdfIn PDF document text
    • http://trevorhannant.com/21679054537.pdfIn PDF document text
    • https://centrumschoolka.pl/photos/file/39575319172.pdfIn PDF document text
    • http://afro-safari.com/upload/files/67577703373.pdfIn PDF document text
    • http://otohondamientay.com/upload/files/63763305634.pdfIn PDF document text
    • http://pensionpoint.cz/userfiles/files/nexul.pdfIn PDF document text
    • http://tugrabilgisayar.net/resimler/files/somituj.pdfIn PDF document text
    • https://thic.muki001.com/plugin/ce1/ckfinder/userfiles/files/35327983794.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161328f72ef093---lamaxokuxuzepixopefolu.pdfIn PDF document text
    • http://bakoca.hu/files/file/relobexoselagexawavuluw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=new+update+pubg+mobile+apkPDF 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_off0000c186.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC186 10756 bytes
SHA-256: 850c1707c3144cf2bb7203c9ad1f29063977c0c6beaa9be53d315dbeb76959b9
font_01_sfnt_off0000d9dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9DD 17228 bytes
SHA-256: c2b11a11074621d00d3fa3b6613282ea6df2abef73d8d96f1b05378077cb8b22
font_02_sfnt_off0001067f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1067F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1