Malicious PDF — malware analysis report

Static analysis result for SHA-256 767a53fc7aeba271…

MALICIOUS

PDF

73.3 KB Created: 2021-09-20 05:57:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 98ddf8ffd31ec34f3004c461b4f4a72a SHA-1: a8e8d4150bd5fb6cf96deaa8fa6cf9e9e0cda2dd SHA-256: 767a53fc7aeba27142926daaa0fa4cce862e90075660d18ed3a5eafd17d634e5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://nomylo.ru/uplcv?utm_term=usb+loader+wbfs
    • http://jfhcoaching.nl/userfiles/files/zowetobulirafovozela.pdf
    • https://www.orthovision-lublin.pl/ckfinder/userfiles/files/vefutofipuzoniso.pdf
    • http://gnatowski.pl/attachments/file/gefabekejudijevuwag.pdf
    • https://reitinguok.lt/userfiles/file/kezogerarojuf.pdf
    • http://hai-bi.com/uploads/files/202109130454066692.pdf
    • http://xn--66-6kc8bfmkmjd.xn--p1ai/admin/ckfinder/userfiles/files/77714462733.pdf
    • http://www.tamtrebinhminh.com/public/files/numurewodupamazu.pdf
    • http://klgd.spokoino.ru/i/upload/files/90533555191.pdf
    • http://samtekelektrik.com/files/45347590280.pdf
    • http://choragwica.pl/userfiles/file/93373889679.pdf
    • http://theorientgarden.iorderfoods.com/uploads/files/15914797999.pdf
    • https://aspit.ro/imagini_ws/21154676287.pdf
    • http://sualpturizm.com/userfiles/file/lelebolur.pdf
    • http://aarogyamedico.com/userfiles/file/58111713002.pdf
    • https://ferdavagnar.is/images/fck/file/nigebigi.pdf
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/4d9dttsg658abmoc0ho260dees/jekofowezetupigajewagan.pdf
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613ceef33711e---82593862554.pdf
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/ddc18faf7c0cf83d855ae616cf25e520/vixonuvibom.pdf
    • https://grancom.by/upload/docs/86832395778.pdf
    • http://marketingnews.fr/images/file/lufuxaletej.pdf
    • http://automsystem.com/UploadFile/file/20210904065648283.pdf
    • https://avenue102.com/uploads/file/nokigexuma.pdf
    • http://northcity.rs/slike/files/84190074088.pdf
    • http://jmestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/60472757277.pdf
    • https://matraci.info/UserFiles/File/70339728082.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_off0000bf91.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBF91 16792 bytes
font_01_sfnt_off0000d7a3.bin
fd2baa1e67ab7d61c20aad81c2890c6e3f95bd122f5d42071823457d25d6f567
pdf-font-stream PDF embedded font (sfnt) at offset 0xD7A3 15840 bytes
font_02_sfnt_off000100d9.bin
4780f298c7aa071512cf5adb9b94575df50818e8d13fdb8f3d8bfe8a50baebed
pdf-font-stream PDF embedded font (sfnt) at offset 0x100D9 10284 bytes