Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8658a4b68c5cf89…

MALICIOUS

PDF

73.7 KB Created: 2021-09-16 03:15:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: dcc48c733ac848f1e3f16b6941f29820 SHA-1: b4ff34b8dd1ef867ef81264e301534afa54766b8 SHA-256: b8658a4b68c5cf8984748975b0f80e616355a07133b20a280de602f2ff2e04e9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, many of which point to disposable hosting and are part of a link farm, indicating a phishing or redirection attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links are consistent with techniques used to redirect users to malicious sites, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • 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.
  • 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://grupahatak.pl/admin/_fck_files/file/tidewilab.pdf In PDF document text
    • http://lev-steklo.ru/userfiles/file/xulidef.pdfIn PDF document text
    • http://baiduvpn.com/upload/files/xitujuwokuba.pdfIn PDF document text
    • https://kohphanganhotelandtour.com/userfiles/file/64507801776.pdfIn PDF document text
    • http://shendaoguoji.com/data/attachment/file/repob.pdfIn PDF document text
    • http://insureavisitor.com/userfiles/file/tinakumugenasemiregono.pdfIn PDF document text
    • http://studiotecniconuti.it/userfiles/files/zisajo.pdfIn PDF document text
    • http://attep.com/home/sandbox/domains/heekee.com.hk/public_html/ckfinder/userfiles/files/73251252435.pdfIn PDF document text
    • https://www.weboonline.com/ckfinder/userfiles/files/mizov.pdfIn PDF document text
    • http://livestocktool.com/d/files/18643147590.pdfIn PDF document text
    • https://zifu-tech.com/app/webroot/userfiles/files/8135007581.pdfIn PDF document text
    • https://absoluteanytime.com/media_file/files/files/93641113323.pdfIn PDF document text
    • http://daydreamspin.com/userfiles/file/3745601221.pdfIn PDF document text
    • https://northcoteplaza.com/userfiles/file/60514295262.pdfIn PDF document text
    • http://hp-cnc.de/uploads/files/logow.pdfIn PDF document text
    • http://edv-denk.com/userfiles/file/gususakenulopotenejijir.pdfIn PDF document text
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/4c21b0398132db9e915118132fa68668/87981142548.pdfIn PDF document text
    • http://newworldss.com/uploads/file/99394677839.pdfIn PDF document text
    • https://travellifeafrica.com/ci/userfiles/files/valimedivir.pdfIn PDF document text
    • http://liebherr-tr.com/userfiles/file/22347189266.pdfIn PDF document text
    • http://elskenecologie.nl/files/zowudek.pdfIn PDF document text
    • https://cyklo-wellness-penzion-palice.cz/content/zokabum.pdfIn PDF document text
    • https://biogenetixpharma.com/ci/userfiles/files/83847839183.pdfIn PDF document text
    • https://quangcaonoithatgiahung.com/admin/webroot/upload/image/files/58083052728.pdfIn PDF document text
    • http://eco-building.cz/UserFiles/File/43611753891.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+set+data+usage+in+notification+barPDF 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_off0000bd74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD74 16340 bytes
SHA-256: aaf9f373c2ab7c1f8f9f0916f2265c821590f7fdc27f753ad88e56c8a00d1653
font_01_sfnt_off0000e76b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE76B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ff82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF82 10924 bytes
SHA-256: b73a0cb4bef993cabafbb32c10c76ed745e1ef7e9e970e8cacd3bd41d5c5d61e