Malicious PDF — malware analysis report

Static analysis result for SHA-256 31e3dc311671574d…

MALICIOUS

PDF

84.1 KB Created: 2021-09-14 07:15:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 39612c487f07e0d643a6e3337114f223 SHA-1: f29024253b24f4363edd500a211e01cecf6641b9 SHA-256: 31e3dc311671574d7113acad030398b7705cc70f326d0bd4c5ace7d693efc5f3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV. The PDF structure contains a link farm, with numerous URLs pointing to other PDF files, suggesting a phishing or malware distribution scheme. The presence of external URIs and the 'disposable link farm' heuristic further support this assessment. No scripts were extracted, but the overall structure and heuristics indicate a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://bertrandetgastineaudesigners.fr/userfiles/file/kaxawifudodekejapiked.pdf In PDF document text
    • http://resetimpianti.it/reset/public/file/bimiresigumomom.pdfIn PDF document text
    • https://jecoexports.com/ckfinder/userfiles/files/ninefuxum.pdfIn PDF document text
    • http://daiwavn.com/uploads/image/files/48133466664.pdfIn PDF document text
    • https://atkarisuli.hu/userfiles/file/46472035656.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139f75811d3f---25440329437.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613a47f8a4305---98484333208.pdfIn PDF document text
    • http://rspon.pl/images/wyswig_images/file/resinuwopevib.pdfIn PDF document text
    • https://www.domosystem.gr/ckfinder/userfiles/files/vexodapidarivofawokam.pdfIn PDF document text
    • http://fazekaskozpont.hu/images/upload/file/22979149566.pdfIn PDF document text
    • http://yangs-ns.com/ckfinder/userfiles/files/20210914071408.pdfIn PDF document text
    • https://calson.garment-pro.com/ckfinder/userfiles/files/56441083221.pdfIn PDF document text
    • http://ohdiabo.net/images/ckeditor/files/3025007803.pdfIn PDF document text
    • http://yugreat.com/filespath/files/20210906172153.pdfIn PDF document text
    • http://zagazzo.com/userfiles/file/febitirabuwirukodozik.pdfIn PDF document text
    • https://www.mftelhas.com.br/adm/Editor/ckfinder/userfiles/files/99117340829.pdfIn PDF document text
    • https://balajihighfields.in/userfiles/file/jasasujipa.pdfIn PDF document text
    • https://webmenuplus.com/images/file/tiwuneroputupujise.pdfIn PDF document text
    • https://semagro-msw.ru/pics/images/file/56778914856.pdfIn PDF document text
    • http://kimyasaldubeller.com/upload/ckfinder/files/99326934634.pdfIn PDF document text
    • https://alubiasdetolosa.com/files/galeria/files/98403040447.pdfIn PDF document text
    • http://balbu.hu/uploads/news/file/fajoparizuxozuwaxade.pdfIn PDF document text
    • http://pribatu.lamilagrosaimport.com/images/files/39149743936.pdfIn PDF document text
    • http://nakajima-ya.com/upload/save_image/files/29013837854.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=prince+of+persia+5+downloadPDF 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_off0000e029.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE029 10736 bytes
SHA-256: de2f8f0659ad5cabaac00e81c3351cc7c0f699b7b102254d336739dab403308e
font_01_sfnt_off0000f902.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF902 19080 bytes
SHA-256: 6a76cd8b4c630baa3ab5ce283885085e490289fce8e1b89c35b244d322d871e0
font_02_sfnt_off00012ac4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AC4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1