Malicious PDF — malware analysis report

Static analysis result for SHA-256 f938b3b04deac548…

MALICIOUS

PDF

77.9 KB Created: 2021-09-15 21:18:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8cc2712177ebdb0d3123477c8a206759 SHA-1: ae490cac5d50787dbd7d9ddacd2fb2bd3ce401d2 SHA-256: f938b3b04deac548c62a23dae946899b0059a083174e3e65b715dda3f0eda0af
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a high number of embedded links pointing to potentially malicious domains, suggesting a phishing or malware distribution attempt. While no scripts were explicitly extracted, the presence of numerous external URIs and the overall detection profile strongly suggest a malicious intent to redirect users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://mediacast.vn/ckeditor/upload/files/nulaguwujawix.pdf In PDF document text
    • http://studioriggio.it/userfiles/files/75137550421.pdfIn PDF document text
    • https://raselapp.com/userfiles/file/kuranilekexubufomobaru.pdfIn PDF document text
    • http://taiwan-tsai.com/upload/files/wirarifuzinenanol.pdfIn PDF document text
    • https://mpressivelabels.com.au/application/third_party/ckfinder/userfiles/files/wijoxamu.pdfIn PDF document text
    • http://cnmrobotics.com/files/files/vafelugobazodisonemozevug.pdfIn PDF document text
    • https://jhservice.net/imagenes/galeria/files/83269029663.pdfIn PDF document text
    • https://www.ebenisterie-burette.com/ckfinder/userfiles/files/63739253319.pdfIn PDF document text
    • https://pensiuneavalentina.ro/app/webroot/file/busanubuda.pdfIn PDF document text
    • https://tskrea.com/userfiles/file/20765176455.pdfIn PDF document text
    • http://doubles301.jp/files/ckeditor/files/14422020022.pdfIn PDF document text
    • http://jiendurancecoaching.com/ckfinder/userfiles/files/77371399248.pdfIn PDF document text
    • http://fthyhs.com/resource/docContentImg/file/2021-09-11/912f62bc975b46c2322021abffe0336e.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613f820982b1f---dugupabab.pdfIn PDF document text
    • http://roycraft.ca/userfiles/file/giverit.pdfIn PDF document text
    • http://usatovl.ru/upload/fckeditorfile/17498239190.pdfIn PDF document text
    • http://livelyway.com/ckfinder/userfiles/files/fulojuziwerudaba.pdfIn PDF document text
    • http://gemculture.com/userfiles/file/63382721429.pdfIn PDF document text
    • http://mfcpavpos.ru/file/pavapotisezitid.pdfIn PDF document text
    • https://thic.muki001.com/plugin/ce1/ckfinder/userfiles/files/92665028506.pdfIn PDF document text
    • http://minhphucvietnam.com/uploads/userfiles/file/badoni.pdfIn PDF document text
    • https://xrtradingfeedback.com/cmsimages/file/52669287757.pdfIn PDF document text
    • http://twgo8.com/uploads/base/files/202109081644147297.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=charlie+and+the+glass+elevator+pdfPDF 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_off0000cb86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB86 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e398.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE398 17516 bytes
SHA-256: 2b845d0ce78a2f5128c7ff2cc06698779f4502e0c3abdd0308f5a39a419c4800
font_02_sfnt_off00011168.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11168 10876 bytes
SHA-256: 3823b4ff06fe590577727c2df9b53d716f035e7673701bd5fe1aa9f35f167207