Malicious PDF — malware analysis report

Static analysis result for SHA-256 b39816069508185c…

MALICIOUS

PDF

89.9 KB Created: 2021-09-03 19:20:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 1598249ce6fac951a6e1398b18a50a38 SHA-1: c4d2e546e3ef88e4161711d3b8cde3d1251855a2 SHA-256: b39816069508185cc97697558550d139ab7813804835b7b53aaf2cc10a793915
156 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. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads. While no scripts were explicitly extracted, the nature of PDF link farms often involves embedded JavaScript to facilitate redirection or exploit vulnerabilities, hence the inclusion of T1059.007.

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://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093d2e8af763---fenev.pdf In PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608912ba95279---98599928551.pdfIn PDF document text
    • http://transinfosoft.com/userfiles/file/88842427267.pdfIn PDF document text
    • http://timelessmebel.ru/wp-content/plugins/super-forms/uploads/php/files/dc051b051771089a3a510d042d82b0fb/59411394778.pdfIn PDF document text
    • https://www.kasekimi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082eaeda1fd4---16902728019.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abee8add5c0---12199207807.pdfIn PDF document text
    • https://dollarplus98.com/images/upload/files/xavoxafopadamobo.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607af0357270b---wadavigotuwaramo.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/d492e70c06a7103579052a3298a2fbb6/kijarofunabojakum.pdfIn PDF document text
    • http://bawaconstructions.com/editorData/file/83559697663.pdfIn PDF document text
    • http://swiss-ex.com/images/blog/file/polid.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f6565d9573---72144304922.pdfIn PDF document text
    • http://geoman.cz/data/file/wixumuvotonozufifor.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bb21121c4ef---ruzolidusiwojuvigejigave.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce27a6d1fe---14702419981.pdfIn PDF document text
    • http://luxmeterthai.com/ckfinder/userfiles/files/55531088984.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/lhr22l07b4d1500ut79567obf6/xesirik.pdfIn PDF document text
    • https://transturist.ba/ckeditor/ckfinder/files/files/voweropin.pdfIn PDF document text
    • http://veno2.com/upload/vigufebezagu.pdfIn PDF document text
    • http://xoblates.com/clients/e/e0/e08cfb93fb97b00c28394d0532709dc9/File/xakezodegepigejoburubar.pdfIn PDF document text
    • http://autowassenindex.nl/images/uploads/46436710618.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/mag8o58ddptv3eqs9kchrs4jha/vetebumubutapewi.pdfIn PDF document text
    • https://fokusmedia.com/images/uploads/60638203594.pdfIn PDF document text
    • http://esejsc.com/upload/files/borifof.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8cebec859a---jofixub.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=ridurre+dimensioni+pdf+anteprimaPDF 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_off0000fa10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA10 10760 bytes
SHA-256: 0639afeb10abcdf2fb45762025d0504fb3bf9ef8517a67cb1b744ebf3cd32463
font_01_sfnt_off000112ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112CA 17756 bytes
SHA-256: d0a17ac7b32d6264f0c5d92bf49238859c8a97e487c4c06e83df9f021b8cb89b
font_02_sfnt_off0001415d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1415D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1