Malicious PDF — malware analysis report

Static analysis result for SHA-256 3937c3c05efd2cd7…

MALICIOUS

PDF

72.8 KB Created: 2021-09-26 00:43:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 23eab0ce8fb9509e7aa14e6cc4a7ed86 SHA-1: 789b58dfdbd1747b2cf44e4af8baa39e3a741b79 SHA-256: 3937c3c05efd2cd7016f14bfbe178ca3dd65a0dc5f85466d45217d39fd8545d2
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which are part of a link farm designed to redirect users to potentially malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 https://kaunas.cvzona.lt/resources/img/files/xapukozude.pdf In PDF document text
    • http://lubrifianti-auto.ro/files/file/3918066208.pdfIn PDF document text
    • http://rivucota.com/upload/files/33892022515.pdfIn PDF document text
    • http://boxerdapolenta.com/cmsimple/images/file/83350550817.pdfIn PDF document text
    • https://ku4ysk-9lgp4y.com/contents/files/74030222487.pdfIn PDF document text
    • https://fedico.ca/upload/editor/file/64876412164.pdfIn PDF document text
    • http://twapp.freshkon.com/upload/files/24398867398.pdfIn PDF document text
    • http://budohurtsa.pl/userfiles/file/55616598747.pdfIn PDF document text
    • https://mcq-exambd.bdbabymart.com/app/webroot/ckfinder/userfiles/files/5904394720.pdfIn PDF document text
    • https://polresseluma.com/assets/ckfinder/core/connector/php/uploads/files/mubiguxodozogud.pdfIn PDF document text
    • http://manuale.aziendasulweb.it/userfiles/files/kinaf.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141d7b0e9ce5---31672555310.pdfIn PDF document text
    • http://neboskreb-irk.ru/uploads/userfiles/files/88907156294.pdfIn PDF document text
    • https://ooo-kenk.ru/userfiles/file/wasizufepimowa.pdfIn PDF document text
    • https://marwaservicecenter.com/nbloom/fckuploads/file/30463891155.pdfIn PDF document text
    • https://inverpalmas.com/aym_image/files/55493641110.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/58151881478.pdfIn PDF document text
    • https://noble-program.site/js/ckfinder/userfiles/files/4987229273.pdfIn PDF document text
    • http://acpiindia.com/userfiles/file/kazababexezojudoxipivevil.pdfIn PDF document text
    • http://gzafjc.com/uploadfile/files/bozupupabepimelipelum.pdfIn PDF document text
    • http://happysmilecard.com/uploads/files/momudasir.pdfIn PDF document text
    • http://www.enjoyvaltellina.it/admin/ckfinder/userfiles/files/razusefexogevini.pdfIn PDF document text
    • http://tdjl.com/uploadfile/file///2021091408075467.pdfIn PDF document text
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/1d5e511b96092bc16e03a1c0fd49b1ba/ligigokedakobolinekipu.pdfIn PDF document text
    • http://laiksmodalux.lt/app/webroot/uploads/userfiles/files/20810364223.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=moving+photos+from+internal+storage+to+sd+cardPDF 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_off0000b7df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7DF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cff6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFF6 11128 bytes
SHA-256: 9567d18217e0889a8176759a22a25f2bb48a023ea6511df4fe7982b659f62ed7
font_02_sfnt_off0000e993.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE993 16956 bytes
SHA-256: a635da135c3bf6e260ca658382aca47b1e04ed96516a87adb304e0c2a10c99e3