Malicious PDF — malware analysis report

Static analysis result for SHA-256 c23bb7f59d27d756…

MALICIOUS

PDF

85.3 KB Created: 2021-09-14 12:08:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e04e8edfb20651f15b259f4993faa11a SHA-1: 98d87b601f231d430080fd0490343666b0d6a719 SHA-256: c23bb7f59d27d756f7d7bbc55b581b3d709f227343c4b7d5c517fa15665ac8d0
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within documents. The presence of numerous external URLs, many pointing to PDF files hosted on disposable domains, suggests a link farm or redirection mechanism designed to lead users to malicious sites. ClamAV and ML classifiers also flagged this file as malicious, indicating a high likelihood of phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://ketchas.ru/uplcv?utm_term=consumo+bateria+android PDF link annotation
    • http://nhatngungoisaoxanh.com/upload/files/12204398282.pdfIn PDF document text
    • http://nature-revive.org/files/file/4615650129.pdfIn PDF document text
    • http://stomerijindex.nl/images/uploads/80522573962.pdfIn PDF document text
    • http://phantasos.org/userfiles/file/60831708868.pdfIn PDF document text
    • http://cokhiminhhien.com/media/ftp/file/serafapit.pdfIn PDF document text
    • http://thegrcinstitute.org/app/webroot/js/ckfinder/userfiles/files/ramewowowironuzugotemogu.pdfIn PDF document text
    • http://www.pvvc.cz/files/jemigag.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/36121387521.pdfIn PDF document text
    • http://arcstema.com/userfiles/files/risadenuzipevetutimusoxu.pdfIn PDF document text
    • https://legyenegyjonapod.hu/userfiles/files/43639211668.pdfIn PDF document text
    • https://himalayanespresso.com/espresso_ckfinder/userfiles/files/pufijimobulisajis.pdfIn PDF document text
    • https://ihappywash.com/uploads/files/202109051653286952.pdfIn PDF document text
    • http://finara-v.com/file_media/file_image/file/17189124713.pdfIn PDF document text
    • https://raovat72.vn/uploads/news_file/bogufurarimoxewaj.pdfIn PDF document text
    • http://agavietnam.com/img/files/falewevulex.pdfIn PDF document text
    • https://strategieb2b.com/userfiles/file/nomulifabunajatuzorolide.pdfIn PDF document text
    • http://helloslow.com/data/userfiles/files/sinuj.pdfIn PDF document text
    • https://dongciao.com/uploads/files/202109080801518622.pdfIn PDF document text
    • http://fastcredit.ge/userfiles/file/nolakumirojexajemiwilopup.pdfIn PDF document text
    • http://sinostandards.net/upload/files/99695890717.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613817e2933be---21321452541.pdfIn PDF document text
    • http://myjobcareer.net/userfiles/file/2021091318385173499.pdfIn PDF document text
    • http://africareview.in/userfiles/file/95488830473.pdfIn PDF document text
    • http://cbcom.fr/ressource/site-image/files/bovetedivotatekol.pdfIn PDF document text
    • https://legacydockandmarine.com/wp-content/plugins/super-forms/uploads/php/files/8b081a363895e08e9b0fd6135bdb5888/24243209577.pdfIn PDF document text
    • 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_off0000e1c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1C9 20288 bytes
SHA-256: a9452d9c8bff5db41669ccff39d0b3124adaf749a1a6eccf481b788cdb72ec72
font_01_sfnt_off00011704.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11704 10632 bytes
SHA-256: 264337ca73403d11ad6f46544b82561d9c897eb506603923bef20805c413db40
font_02_sfnt_off00012f5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F5D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1