Malicious PDF — malware analysis report

Static analysis result for SHA-256 3901d228fe3bb2d4…

MALICIOUS

PDF

68.8 KB Created: 2021-09-28 05:01:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b94f3d551ab675cec9bb2e25bc7f8ca5 SHA-1: 315c65430e7cd1d3615079cdc42e193edae3ed89 SHA-256: 3901d228fe3bb2d4716c0229f2607a75f41fa6fbfbdb79b414ba0b953a02f0e8
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF is identified as a phishing lure due to its image-only nature and embedded clickable action. It contains numerous links to external PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://coral-travel66.ru/admin/ckfinder/userfiles/files/9639799114.pdf In PDF document text
    • http://autoscuolecasetta.it/userfiles/files/widujutipizuwisuwidob.pdfIn PDF document text
    • https://msiutilities.net/documents/xidoz.pdfIn PDF document text
    • http://daiduongmetal.com/uploads/ckfinder/files/zegunex.pdfIn PDF document text
    • http://ferrocom-spb.ru/userfiles/files/71421795785.pdfIn PDF document text
    • http://cheliabinsk.realxenon.ru/uploads/files/90648475547.pdfIn PDF document text
    • http://med-os.com/user_upload/file/34912701441.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/302cf65360e6eebda1619ff2d2184f10/45728725737.pdfIn PDF document text
    • http://jinsonmetal.com/Upload/file/wejomosivajinodad.pdfIn PDF document text
    • https://www.agcontraincendios.es/ckfinder/userfiles/files/45406647548.pdfIn PDF document text
    • http://nhasachconggiao.com/luutru/files/23810812121.pdfIn PDF document text
    • http://soft-pro.hr/upload/datoteke/97869512438.pdfIn PDF document text
    • https://www.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/35357526740.pdfIn PDF document text
    • http://xszhuhai.com/uploadfiles/files/49244889133.pdfIn PDF document text
    • https://dewalt-naradi.cz/media/upload/editor/file/76522140001.pdfIn PDF document text
    • https://perkunasstudio.com/uploads/files/202109262157206956.pdfIn PDF document text
    • http://hamkr.com/userData/board/file/jemikus.pdfIn PDF document text
    • https://afra24.com/basefile/afra24/files/zujilobuwanuvikovuver.pdfIn PDF document text
    • https://conexkarvan.com/cache/fck_files/file/25300891577.pdfIn PDF document text
    • https://chrmglobal.com/userfiles/file/59255634570.pdfIn PDF document text
    • https://kamwalibais.com/userfiles/file/12166199512.pdfIn PDF document text
    • http://naoshima-tours.com/images/blog/file/lategatefa.pdfIn PDF document text
    • http://actybrain-consult.com/Upload/files/21340808655.pdfIn PDF document text
    • http://lechioutdoor.com/userfiles/file/59486466379.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=download+gta+v+for+android+for+freePDF 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_off0000b1db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1DB 10516 bytes
SHA-256: b426a4f940b42831d8ac0b2191d48be82a3f70cc07f1badfcf0fbbb039ef0557
font_01_sfnt_off0000c9bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9BD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e1cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1CF 14076 bytes
SHA-256: d7f84417a1b8100acd5fe22e7205df4c86715cefa237bd8c0fdc5556fc600024