Malicious PDF — malware analysis report

Static analysis result for SHA-256 16e1d781a03fac3b…

MALICIOUS

PDF

83.4 KB Created: 2021-09-17 11:30:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bf10278336b3aab4e349acbbd4deec2a SHA-1: af46eb59057acdd353bb55a3e2d8cb9e7c394e4c SHA-256: 16e1d781a03fac3b82dbed77ce50f18fdf8cd31318c9b741d0ac07484ee2a785
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous other PDF files hosted on various domains, many of which appear to be compromised or disposable. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The presence of multiple external URIs and link farm heuristics supports the conclusion that this document is a lure to redirect users to malicious content.

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://livstyle.ro/home/livstyle/public_html/uploads/files/gaxatatizafunurokuga.pdf In PDF document text
    • https://dpt-mh.com/uploads/news/files/xalixejibawezomiv.pdfIn PDF document text
    • http://librojuridico.com/aym_images/files/birerisuteluxefurexep.pdfIn PDF document text
    • http://yangs-ns.com/ckfinder/userfiles/files/20210916065909.pdfIn PDF document text
    • http://jsushibrea.com/uploads/files/bidoxed.pdfIn PDF document text
    • http://chekeeh.ir/basefile/chekeehir/files/67716180981.pdfIn PDF document text
    • http://ambiance-cinema.fr/wp-content/plugins/super-forms/uploads/php/files/703034294d56fac355c6bd3fd5950d66/dazukodikonunole.pdfIn PDF document text
    • http://wsp.pl/userfiles/file/kumoludarovugigom.pdfIn PDF document text
    • http://ksiclubbiz.ksiclub.org/svnprojects/DHD/Source/images/files/13081000460.pdfIn PDF document text
    • http://imreelectric.sk/uploads/file/91026279974.pdfIn PDF document text
    • https://mmoxx.mn/userfiles/files/38941782493.pdfIn PDF document text
    • http://konyanincigkoftecisi.com/userfiles/file/fanatexemetazanapovin.pdfIn PDF document text
    • http://koreabulk.net/userData/board/file/59860320240.pdfIn PDF document text
    • http://oilspecchem.com/files/ladivalujepijiri.pdfIn PDF document text
    • http://agavietnam.com/img/files/70291839154.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133f10bf2c8c---tefemofilizele.pdfIn PDF document text
    • http://sinosteelcode.com/filespath/files/20210910144808.pdfIn PDF document text
    • http://studiodugnani.it/userfiles/files/10896596264.pdfIn PDF document text
    • https://venus-forever.com/image/files/kenolapor.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/16143e579e9686---vaxiso.pdfIn PDF document text
    • http://nceed.kr/pds/userfiles/files/12499852365.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16139787cdf81f---60550040127.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=shortcut+for+clearing+history+chromePDF 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_off0000dd1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD1F 18876 bytes
SHA-256: 5530bd58f9b6dc5589edfff61331c8a90eb573b4ceff93b96b31e06fe5cb9e7b
font_01_sfnt_off00010e22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E22 11072 bytes
SHA-256: e41a4f29edeb24dd26592e4073838ec9276936c2a716e86cc0b4778d4e92830a
font_02_sfnt_off000127c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1