Malicious PDF — malware analysis report

Static analysis result for SHA-256 256984aa16217cd0…

MALICIOUS

PDF

78.7 KB Created: 2021-09-13 20:44:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: c7adeeaddb1c9a750757100af7ab74a5 SHA-1: 05009337d3ecd9a3d968c55f41a5d94275af4ec9 SHA-256: 256984aa16217cd05a3fe5db900c34955841fea7d12be358367e9e90e1a4a2a7
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and numerous external URIs, flagged by ML and ClamAV as malicious. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a link farm structure, suggesting the document's purpose is to redirect users to potentially harmful sites. The embedded JavaScript likely facilitates this redirection or further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://xn--brneneskontor-landsforening-b0c.dk/userfiles/file/89004460865.pdf In PDF document text
    • http://eclickapps.in/userfiles/files/96369291791.pdfIn PDF document text
    • https://www.willmarshelter.com/ckfinder/userfiles/files/duwavunijamodanujiruguw.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/1613654c040fcf---woxoti.pdfIn PDF document text
    • https://lensmam.com/userfiles/file/disali.pdfIn PDF document text
    • https://vroa.pl/chplusfiles/file/fipufate.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/wezezejikurusepap.pdfIn PDF document text
    • https://hanoihome.net/img_duhoc/files/3603687838.pdfIn PDF document text
    • http://sreema.org/FCKeditor/file/80041629993.pdfIn PDF document text
    • http://karat-dobremiasto.pl/userfiles/file/46677187927.pdfIn PDF document text
    • http://nakloboucku.cz/uploaded/file/18610951444.pdfIn PDF document text
    • http://kunbot.com/upload/files/netepusa.pdfIn PDF document text
    • http://peterpan1996.it/userfiles/files/bolonifufejefagovirego.pdfIn PDF document text
    • http://www.msjcongregation.org/www/js/ckfinder/userfiles/files/10984410683.pdfIn PDF document text
    • https://btsis.com/upload/ckfinder/files/96782513294.pdfIn PDF document text
    • http://qbcar.ru/ckfinder/userfiles/files/rafaduvimeperida.pdfIn PDF document text
    • http://krukaiart.com/userfiles/files/7101575420.pdfIn PDF document text
    • https://cabsfromheathrow.com/userfiles/file/saxive.pdfIn PDF document text
    • http://chongros.com/userData/board/file/tonakedafaja.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ede2c18e70---2472051669.pdfIn PDF document text
    • https://petribax.com/userfiles/file/jarenetagoxud.pdfIn PDF document text
    • http://abwcolley.com/uploads/files/doparirorokizudeso.pdfIn PDF document text
    • http://piemonteforyou.it/userfiles/file/97647858092.pdfIn PDF document text
    • http://contelex.it/userfiles/files/81306195715.pdfIn PDF document text
    • https://www.moxiclear.com.au/application/third_party/ckfinder/userfiles/files/24071921202.pdfIn PDF document text
    • https://weborder.cloud/userfiles/file///levaxamipobitevitideb.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=android+emulate+bluetooth+keyboardPDF 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_off0000cec8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEC8 17336 bytes
SHA-256: 610808bc9da39519f0c6a03d83c7360521c6ca264b980424c7ed5a43214ea77f
font_01_sfnt_off0000fbe9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBE9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011400.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11400 10772 bytes
SHA-256: 1dd2b90482a19b7542ff358ccf1c85c978a5a7e4929b8d90c954047cb74059a0