Malicious PDF — malware analysis report

Static analysis result for SHA-256 192339dd087537b0…

MALICIOUS

PDF

77.3 KB Created: 2021-09-13 11:33:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 93f31d05275da2ca53bfc0303c113566 SHA-1: 7552efbcd2850901b340333911337c21075adfbc SHA-256: 192339dd087537b0b5ce981e2b851e2b00a06967dcd85115ea53f31027053f3d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous links to external websites, many of which are hosted on disposable domains or compromised CMS upload directories, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or distributing malware via these links. No scripts were extracted, and the document body was unreadable, so the primary attack vector appears to be the embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://tnslib.tools/userfiles/files/71725915611.pdf In PDF document text
    • http://studioambienteterritorio.it/userfiles/files/47678507847.pdfIn PDF document text
    • http://alajwakh.com/uploaded_files/userfiles/files/bunefenu.pdfIn PDF document text
    • http://daglichtfilters.nl/ckfinder/userfiles/files/lekiliruvakixitorek.pdfIn PDF document text
    • http://2990592.ru/ckfinder/userfiles/files/79326944359.pdfIn PDF document text
    • http://thechitay.com/uploads/userfiles/file/44393659326.pdfIn PDF document text
    • https://stop-remont.ru/ckfinder/userfiles/files/vabatufedib.pdfIn PDF document text
    • http://edwardfmcgintypa.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/notenifapavejozelipo.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613bb984c87ee---lonadiwufeb.pdfIn PDF document text
    • http://camelliafb.com/uploads/files/202109031527471439.pdfIn PDF document text
    • http://ingore.cn/upload/files/bifoxirafuwulosuj.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/32e5f23d50e8531dd82b131f7d796a0f/pekinisezowetomonegawan.pdfIn PDF document text
    • http://tucholainfo.pl/userfiles/file/gufebiri.pdfIn PDF document text
    • https://alves.bg/ckfinder/userfiles/files/76201712732.pdfIn PDF document text
    • http://www.hangmandigital.com/files/file/nofizamogofifuvutararugaz.pdfIn PDF document text
    • http://tlumacz-lipno.pl/pdrzewiecki/files/5327908872.pdfIn PDF document text
    • https://it-remarketing.pl/app/webroot/media/files/45017559950.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/qsbdlifav017ik4cso4c5ivab0/27985421508.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/80f022e5a7f8b154a3de79aabc4411c8/32902609585.pdfIn PDF document text
    • https://035620126.tw/upload/greenkitchen/files/xerepokawitopofisajo.pdfIn PDF document text
    • https://mitrasuksesku.com/userfiles/file/wejatizozegadekagafonor.pdfIn PDF document text
    • http://onlineticketreview.com/images/file/3465883165.pdfIn PDF document text
    • https://cursosadistanciayonline.com/medios/files/kewapudunago.pdfIn PDF document text
    • http://pressvaluation.net/FCKeditor/editor/filemanager/connectors/userfiles/file/borewufunele.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=asphalt+8+apk+offlinePDF 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_off0000ca17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA17 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e22e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE22E 10636 bytes
SHA-256: 87c0ef67f8676c8fa9d79a50dde797204bff962957993146b04f49d916cd6470
font_02_sfnt_off0000fa8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA8C 17284 bytes
SHA-256: 72c70b1b0b645c98c2c75171b3babc8f77a67c523d77efbcce8ba1569ffeedf7