Malicious PDF — malware analysis report

Static analysis result for SHA-256 fae84ee8d0c5e432…

MALICIOUS

PDF

82.1 KB Created: 2021-09-02 05:18:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 46e48e0a1978220dd515d7463097a5ea SHA-1: 54ae6cafedfc19cc41e736559308a18b2ad89750 SHA-256: fae84ee8d0c5e432a3e66f1a740ce4a5a92aedbc1ee45ce1978b3bd30f0001f9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous URLs pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking clear user-facing text but containing structural elements indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://krisoc.ru/uplcv?utm_term=an+example+of+autonomy
    • http://muzycznescyzoryki.pl/userfiles/file/bovipoberesezufokoro.pdf
    • http://supermarketdv.ru/files/file/98077711939.pdf
    • https://hohsingfiber.com/ufiles/files/69161155921.pdf
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b9606f2eb2b---51748455764.pdf
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609a14c704df8---nabobixevomakuxe.pdf
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/a8025279c230455d68f8043bd10f64ea/deselasuxedosozexugi.pdf
    • https://hssanesteban.cl/files/joluvisijedi.pdf
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607df3d45079e---nupuz.pdf
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16081590876b89---76802511501.pdf
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/4ac4ee2fb9935f98b9d009795eb751ce/20680386148.pdf
    • http://studiodugnani.it/userfiles/files/12895963705.pdf
    • http://elesi.eu/fichiers/files/begisezawufabemanof.pdf
    • http://ottotech.center/userfiles/file/2834467183.pdf
    • http://kenshopvn.com/uploads/files/derusefafu.pdf
    • http://xn--9n2bn9mz3aba29g44r4o0a.kr/fckeditor/userfiles/image/49923581242.pdf
    • http://mitcostruttori.it/userfiles/files/jivelunuweraxemevunevopas.pdf
    • http://micronforgacsolo.hu/UserFiles/file/87040704797.pdf
    • http://world-spa-resorts.com/dok/sinikekobozowot.pdf
    • http://ascensionchina.com/userfiles/file/21205304743.pdf
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160a8e7b89dc67---49714948702.pdf
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4d32e2efa---40070675509.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_off0000e178.bin
10747df68053403ae4e9cd8e1a10e83d83dc1f50f22793b1f208eb7858162ef7
pdf-font-stream PDF embedded font (sfnt) at offset 0xE178 10456 bytes
font_01_sfnt_off0000f94a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF94A 16792 bytes
font_02_sfnt_off0001115c.bin
1f9b6811cf32de6d613fb82e8024be4d0ec64510220fa34b334ecb101d8d0a50
pdf-font-stream PDF embedded font (sfnt) at offset 0x1115C 15992 bytes