Malicious PDF — malware analysis report

Static analysis result for SHA-256 b59d81b3b75f57af…

MALICIOUS

PDF

80.9 KB Created: 2021-09-18 14:38:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5b8e86ebb76bc85701a5aec6200e7b70 SHA-1: f7ece5eae99777356400eb585616af0166e93694 SHA-256: b59d81b3b75f57af5bee411ddf2cc822497e428c61e7589c9a2a57821ccc6fa5
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document is classified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The 'SE_BROWSER_INSTALL_LURE' heuristic strongly suggests the document is designed to trick users into installing malicious browser extensions or updates. While no scripts were explicitly extracted, the presence of numerous external URLs, many pointing to PDF files on potentially disposable domains, supports a phishing or malware distribution scheme. The document's content, though heavily obfuscated in the provided excerpt, likely contains further social engineering elements to facilitate the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://archism.ru/uplcv?utm_term=how+to+add+addons+in+chrome+android PDF link annotation
    • https://jeanmarcrobion.fr/userfiles/file/6111411482.pdfIn PDF document text
    • http://upakuika.com/img/file/gujirotawajiko.pdfIn PDF document text
    • http://g-shocktou.com/user_file/file/18283145304.pdfIn PDF document text
    • http://www.petersonassoc.com/emailimages/file/74058686076.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161428855ec17f---bonarinagexerev.pdfIn PDF document text
    • http://ildong.org/sa_upload/userfiles/file/20210913165050.pdfIn PDF document text
    • http://tienphat.vn/imagesflashupload/file/mevizifazu.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/65672922140.pdfIn PDF document text
    • http://elesi.eu/fichiers/files/66841586630.pdfIn PDF document text
    • http://jtg-antracyt.pl/files/file/vilukitawipogofonov.pdfIn PDF document text
    • http://tries.cz/media/images/upload/file/tekebila.pdfIn PDF document text
    • http://premo.at/userfiles/file/38342235275.pdfIn PDF document text
    • http://reklamavysocina.cz/UserFiles/File/62498542069.pdfIn PDF document text
    • http://vitacanes.com/uploads/files/kawilisepowonaz.pdfIn PDF document text
    • http://huerural.com/uploads/image/files/fipolosasejutopenaxipoluk.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/adb1a600b4d47732c3650d3c4220a973/72695191831.pdfIn PDF document text
    • http://nemeckystrakac.sk/editor_uploads/files/komumiruwodumasosuloxumi.pdfIn PDF document text
    • https://abzesolar.com/uploads/files/99508032270.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/4327660757.pdfIn PDF document text
    • http://likuidart.com/files/ckeditor/files/28797200711.pdfIn PDF document text
    • http://ketnoikienthuc.com/upload/files/goragasurasubojiredira.pdfIn PDF document text
    • http://dautuck.com/uploads/userfiles/file/vojeriwofesekuwowofozi.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_off0000d7a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7A3 17536 bytes
SHA-256: 11519038fb12f822e5084262e63b59dddbf8cc123667a6126537acc28050d372
font_01_sfnt_off00010554.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10554 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D6B 10668 bytes
SHA-256: 9ec20e755307b006e3e66a78163695bcc33683566aa294e657793a262044ca10