Malicious PDF — malware analysis report

Static analysis result for SHA-256 d349cdc57c53a0d2…

MALICIOUS

PDF

76.8 KB Created: 2021-09-12 11:56:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 22a950ad539fc31890bc5381536fcbc8 SHA-1: 7e08bb22e32221959a43bbb3a791779e9154e2b2 SHA-256: d349cdc57c53a0d2a215f86138a697a682da43cec742a511d68bad02bed93654
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution attempt, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://smartmedia.ro/app/webroot/files/userfiles/files/47659221509.pdf In PDF document text
    • http://gerd-pollak.de/userfiles/file/napezutegikenedow.pdfIn PDF document text
    • http://dianacb.cz/userfiles/file/mizawopore.pdfIn PDF document text
    • http://racecross.com/upload/edito_fckeditor/file/jeraxaxojexobukodewoxixor.pdfIn PDF document text
    • https://vietucmould.com/img-vietuc/files/1206153867.pdfIn PDF document text
    • http://sushrutproctology.org/ckfinder/userfiles/files/74307473315.pdfIn PDF document text
    • http://monteconsultants.com/image/upload/File/99733489638.pdfIn PDF document text
    • http://speckletrack.com/update/editor/file/78540133739.pdfIn PDF document text
    • https://kingdomofgodmn.org/userfiles/files/49915807332.pdfIn PDF document text
    • http://seattleteriyaki3.com/uploads/files/vezeranekigenazo.pdfIn PDF document text
    • https://peintures-descours.fr/fichier/files/96857365456.pdfIn PDF document text
    • http://baozhaopharm.com/upload/files/24710472314.pdfIn PDF document text
    • https://giant-nano.com/app/webroot/userfiles/files/30833900772.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/parusexezixotekufumoman.pdfIn PDF document text
    • http://atel-j.nl/uploads/files/muvub.pdfIn PDF document text
    • https://ijieet.org/ckfinder/userfiles/files/93016127907.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/161380feb10d06---82747527682.pdfIn PDF document text
    • https://vayamcs.com/content_files/files/85538313978.pdfIn PDF document text
    • http://agenziaimmobiliarecannavo.eu/userfiles/files/tepegemetisusanixa.pdfIn PDF document text
    • http://dobermanncz.eu/files/97438828830.pdfIn PDF document text
    • http://instalater-macecek.cz/klienti/devel/sneznerolby.cz/ckfinder/userfiles/files/61769151837.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=free+play+store+downloadingPDF 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_off0000ca96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA96 10744 bytes
SHA-256: 6d08c8f54e815d9a586570681942e224e3cc0db2858696fbe9b9cf741de4cf34
font_01_sfnt_off0000e33d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE33D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fb4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB4F 16624 bytes
SHA-256: 30a0403c007f4cb42ab50daacc7297b08d446fa77e8a6e2d0924ac0e35cfeb4d