Malicious PDF — malware analysis report

Static analysis result for SHA-256 81a6e12e919344a0…

MALICIOUS

PDF

85.7 KB Created: 2021-09-04 03:58:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e5efcff65b2a74f82f9a19fe990a847c SHA-1: ebdc215e0d36f1605fc6a6dcfa131b1b0d89500a SHA-256: 81a6e12e919344a0623883e8a87145bf9fcc324959e93ea5669a3b76a4f3c7c4
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised websites and disposable hosting, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, as does the PDF_URI heuristic pointing to a potentially malicious URL.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://itnetworkconsultingsf.com/helpdesk/app/webroot/img/userfiles/files/96789744706.pdf
    • http://scandirent-new.ru/uploads/assets/file/20268875847.pdf
    • http://alexlunacoach.com/img/editor/file/45109012455.pdf
    • https://farmaciasacoor.com/site/upload/file/wonawirudelaza.pdf
    • http://stavebnevyrobky.sk/www/upload/files/letemilujupunal.pdf
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160983c13e8599---butogutopovirozorow.pdf
    • http://sushinamu.com/uploads/files/jufapezo.pdf
    • http://aquamedia.cn/ckfinder/userfiles/files/lonoxajokekobazekax.pdf
    • https://www.azembay.com/wp-content/plugins/super-forms/uploads/php/files/od6aqdpoid1i1gctfp2lv39f3t/39343812649.pdf
    • http://crm333.com/documentos/file/lejolifulixi.pdf
    • https://pjkconstruction.ca/images/file/33611087421.pdf
    • https://eastoncn.housemember.com/uploads/files/45448321900.pdf
    • https://tranthachcaodanang.com/uploads/image/files/piwazumez.pdf
    • http://hauptlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xutos.pdf
    • http://avs-market.ru/admin/ckfinder/userfiles/files/57150528646.pdf
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/7075439eb5f0f59e98886e3819f8d632/116571724.pdf
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/25chof566hmial71o422peslf0/74571162652.pdf
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16094a1db890de---natajorurazoxi.pdf
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a13872be843---92272400492.pdf
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1606eb2f395305---32181659605.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1608e24269b38e---62497270581.pdf
    • https://bhandarisurgical.com/ckfinder/userfiles/files/lipudakuxusi.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=family+therapy+theories+and+techniques+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e99c.bin
78b441f6299ecf3688e0f7a3a0d368fb611e87571b46ec5ac8c2565572ce6236
pdf-font-stream PDF embedded font (sfnt) at offset 0xE99C 11220 bytes
font_01_sfnt_off00010378.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10378 16792 bytes
font_02_sfnt_off00011b8a.bin
eaa603f8d950800fdd6db5bb4b6cfe6a6990c6cb2a2921498409afac750ddece
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B8A 17672 bytes