Malicious PDF — malware analysis report

Static analysis result for SHA-256 def384b558fb16bc…

MALICIOUS

PDF

70.3 KB Created: 2021-10-03 00:37:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 81b3f0e87f5b27ce06ee468c8117e638 SHA-1: 73ef6f65d66648cf52999ac4b9f84541b16b8bd8 SHA-256: def384b558fb16bc596c323fea7cb42051bcc0134e84d54b9790140983afe80d
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload locations, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple PDF-specific heuristics related to URI and link farms supports this assessment.

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 http://gddfboiler.com/uploads/files/bokulesobidawe.pdf In PDF document text
    • http://locthanhroyal.com/upload/files/69298809158.pdfIn PDF document text
    • http://ghibms.com/userfiles/files/28311519827.pdfIn PDF document text
    • http://fygl.net/uploads/file/062121007340.pdfIn PDF document text
    • http://parfumland.sk/upl/bawibanoxaxoluv.pdfIn PDF document text
    • http://archiwum.wyryki.eu/admin/ckfinder/userfiles/files/36717240251.pdfIn PDF document text
    • http://xn----8sbemnkjd7bfu.xn--p1ai/design/img/upload/file/78452400678.pdfIn PDF document text
    • http://vncdata.net/app/webroot/uploads/files/9087783961.pdfIn PDF document text
    • https://milorem-service.ru/userfiles/file/zejakigedadezomapovoj.pdfIn PDF document text
    • http://diamantina-joaillerie.com/ckfinder/userfiles/files/petujoredinidorudokomore.pdfIn PDF document text
    • https://didacostruzioni.it/userfiles/file/64399920492.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/161526021e1732---32849193106.pdfIn PDF document text
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/13339814560.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/161488e4aa8af1---67678927378.pdfIn PDF document text
    • http://officinedesign.it/userfiles/files/jizuzanogage.pdfIn PDF document text
    • http://danieldesignpro.com/userfiles/89030238171.pdfIn PDF document text
    • http://quetthe.com/upload/files/92058921203.pdfIn PDF document text
    • https://kindliving.org/wp-content/plugins/super-forms/uploads/php/files/tmp/dogiximed.pdfIn PDF document text
    • https://pet-fashion.ro/mm/file/tipijasojukiwafotomonuma.pdfIn PDF document text
    • https://valstybestarnyba.com/upckfinder/files/11407101921.pdfIn PDF document text
    • http://netmutum.com/userfiles/file/gosupazijili.pdfIn PDF document text
    • http://uralinteh.com/uploads/files/lopodifizi.pdfIn PDF document text
    • http://milkyway-vn.com/upload/files/peresuwe.pdfIn PDF document text
    • https://jotelek.hu/files/file/23943088667.pdfIn PDF document text
    • https://slotpt2.com/contents/files/52020502807.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=pdf+convert+to+excel+onlinePDF 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_off0000b126.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB126 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c93d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC93D 10308 bytes
SHA-256: ddbf1725b20202fcc549f22d45c80fcb411b1c639d77ef11846d78f33bbdf54c
font_02_sfnt_off0000e093.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE093 16808 bytes
SHA-256: 475a3aaf32a2de8f481be53454e6097dbc70258f913ee7849dc635c6311236e8