Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d6be791d20c8f1b…

MALICIOUS

PDF

84.4 KB Created: 2021-09-07 01:03:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 04a3ff878c8df1767e0b8ae660280268 SHA-1: b84db66a397a8cf961fd6573b847785c3e832678 SHA-256: 5d6be791d20c8f1bce4668bc26a5e9f44399fe66969101a8060b2016b86ef988
156 Risk Score

Malware Insights

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

The PDF document was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier, indicating malicious intent. It contains a link farm with numerous URLs pointing to PDF files hosted on compromised CMS upload directories, suggesting a phishing or SEO poisoning campaign. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the presence of these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://tsg-vaganovskoe.ru/ckfinder/userfiles/files/97896081537.pdf In PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/4d430f0be97bd5db53721592a3bad829/kulizakibopo.pdfIn PDF document text
    • https://alutat.com/data/file/fesivenipotev.pdfIn PDF document text
    • https://planet-for-events.de/userfiles/file/37799291648.pdfIn PDF document text
    • http://au-zlato.sk/upload/files/98813768087.pdfIn PDF document text
    • http://westernmaki.com/uploads/files/37943990565.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/d03bhd80h6b6r2gh8mrjpcgr8v/fewele.pdfIn PDF document text
    • http://jayeonrak.com/upfile_editor/2021/files/vefukaxav.pdfIn PDF document text
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/2037c4b8a776e3ae7d4c660104fc5dc3/54854465689.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/c16c08ec2c6066f69298ab9fc57369e9/temowadi.pdfIn PDF document text
    • http://ing-ka.com/user_img/file/salalemiwugaxigaxola.pdfIn PDF document text
    • http://mallenmediations.com/mallenmediations/images/userfiles/file/ruxiradax.pdfIn PDF document text
    • https://dongphuchuytai.com/upload/files/94305793149.pdfIn PDF document text
    • http://solemarservizi.it/userfiles/files/60910412880.pdfIn PDF document text
    • http://www.morrisjones.co.uk/EditorImages/file/zovopovosobigekewud.pdfIn PDF document text
    • http://tecnoservizi.com/userfiles/files/7728679828.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/16081450ac1a16---vatizeg.pdfIn PDF document text
    • http://otohyundaidanang.com/uploads/image/files/joxaroxuxa.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1609eddb61d8c3---2236668369.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160bc243c1a6c5---99706282354.pdfIn PDF document text
    • http://kamerton.nl/clientfiles/nejifuzugudopomikepef.pdfIn PDF document text
    • https://jclifeschools.org/wp-content/plugins/super-forms/uploads/php/files/c673492b02c821dde0e46f4126d09ab3/wozanutadaxi.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16115a4a1992f8---pufigavozerufob.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/98425b084c8a54a520dcfa9be5571641/4267875089.pdfIn PDF document text
    • https://eventaipei.com/upload/files/kiboroba.pdfIn PDF document text
    • http://mesterek.net/tmp/74959612729.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=belajar+percakapan+bahasa+inggris+sehari+hari+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_off0000e71d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE71D 16416 bytes
SHA-256: 608a76f59dc75a765c1da013825d73026b6776d63a36347425853ed7bdb1d442
font_01_sfnt_off000111c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111C2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000129d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129D9 11096 bytes
SHA-256: 02bb69e5c9a5cc50c7c1be88495093c718765020aeca18f1e2cdcd57dde79533