Malicious PDF — malware analysis report

Static analysis result for SHA-256 4577ef7a35f4e057…

MALICIOUS

PDF

75.9 KB Created: 2021-09-13 17:51:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 0e5f0afab9b4b4297f67dcdcc48cce3d SHA-1: 540779d85396dc9a26341fe716743cf187b22a18 SHA-256: 4577ef7a35f4e05720632c255335cbecbb2d3e566505731c0ffc26c140b48422
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is designed to host numerous links on disposable domains, a common tactic for phishing or distributing further malware. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the link farm heuristic point towards an attempt to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/e1h2imsagnk51du70885hvg9j0/95980642185.pdf In PDF document text
    • http://olgapolyakova.de/files/files/xibapizukifunug.pdfIn PDF document text
    • https://wendi101.com/userfiles/file/mujafet.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613618b02a1e8---dibofonus.pdfIn PDF document text
    • https://www.ojchamber.com/ckfinder/userfiles/files/gabiwewodumafijajaxasupun.pdfIn PDF document text
    • http://studioschicchi.eu/userfiles/files/nafufesiveg.pdfIn PDF document text
    • http://elitsatodorova.com/uploadfiles/file/79310721628.pdfIn PDF document text
    • http://rjbmachinery.com/d/files/302824560.pdfIn PDF document text
    • https://wtmasonry.com/ckfinder/userfiles/files/xapapebeza.pdfIn PDF document text
    • https://rabudiagnostic.com/userfiles/files/nuboxaziralidokok.pdfIn PDF document text
    • http://rld-carbon.ru/file/nifitudalinevibowafidaz.pdfIn PDF document text
    • http://ckm-machinery.com/userfiles/files/semugelape.pdfIn PDF document text
    • https://totalsewa.com/userfiles/file/gifefidaxakotukosazeli.pdfIn PDF document text
    • https://idosekotthonaveresegyhaz.hu/files/files/83581101213.pdfIn PDF document text
    • http://www.globalnautique.nl/upload/files/basetofebu.pdfIn PDF document text
    • http://raffaelecavazzoni.com/userfiles/files/dibarexalosazus.pdfIn PDF document text
    • http://assytekservizi.com/userfiles/files/94735210732.pdfIn PDF document text
    • http://dientrotiendathc.com/media/ftp/file/rituluwuxizefi.pdfIn PDF document text
    • http://consoles-a-gagner.com/fckeditor/userfiles/file/majalubejomin.pdfIn PDF document text
    • https://akproauto.com/nbloom/fckuploads/file/pulatidigebaxuzexaxiw.pdfIn PDF document text
    • http://koreaseals.com/ckfinder/userfiles/files/94800929876.pdfIn PDF document text
    • http://mayphatdienngocquang.com/media/ftp/file/46970255209.pdfIn PDF document text
    • http://www.kevimotor-rock.hu/files/files/belikamejazofa.pdfIn PDF document text
    • http://195exim.com/datas/files/robabijovipizufodadotalil.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=basic+pharmacology+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_off0000c306.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC306 17528 bytes
SHA-256: c5bb06370f66294463b94349ce374c2d10f8a83fd2a255c972f848e67b85af26
font_01_sfnt_off0000f07b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF07B 11132 bytes
SHA-256: e856f689ce4c35d9d8888a157bb3f225d022969a5295693102552137b9b5fb93
font_02_sfnt_off00010a13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A13 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1