Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6acf3cd5183301b…

MALICIOUS

PDF

78.0 KB Created: 2021-10-10 04:26:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 3ce0002f7e34b541da6fa96fc142b8e1 SHA-1: 7e1e1d7d00d960ad377be54eaa9e80723fdc2a05 SHA-256: a6acf3cd5183301b7b9bbe998c2014ef3cf14cc3103703f48625bb3f7b2b1a3e
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS uploads and disposable hosting, indicative of a link farm designed to phish or distribute malware. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were extracted, the structure and URL patterns are consistent with a malicious document used for initial access.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://madiran-cruduparadis.fr/ckfinder/userfiles/files/16653460004.pdf In PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614cd245bc085---9819371540.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615ae1c7f253f---duvuzagexof.pdfIn PDF document text
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/161361e122a9c1---rumoxorupejixa.pdfIn PDF document text
    • http://geyikkimya.com/userfiles/upload/file/74900061317.pdfIn PDF document text
    • https://sanvexe.vn/webroot/img/files/sisojemufedido.pdfIn PDF document text
    • http://fobas.cz/userfiles/file/mojome.pdfIn PDF document text
    • http://reopen911.info/media/file/11577866842.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/kupafet.pdfIn PDF document text
    • http://mgocsm.in/userfiles/file/wokuvajunoderijugisaw.pdfIn PDF document text
    • https://navliecky.net/userfiles/file/10741580361.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/9dvdugijiu2se7npigtlne3mjh/vefiramiwetokivatet.pdfIn PDF document text
    • https://universitecentrale.net/uploads/FCK_files/file/67123189295.pdfIn PDF document text
    • http://xn--49s538bo8ux8c.net/userfiles/file/14857831897.pdfIn PDF document text
    • http://www.tecs4.com/intranet/ckfinder/userfiles/files/8384410404.pdfIn PDF document text
    • https://www.loisirs-auto-occasion.fr/ckfinder/userfiles/files/nazuvegifizogatapuba.pdfIn PDF document text
    • https://semut73.com/contents/files/45460504317.pdfIn PDF document text
    • http://fiorenzuolatrack.it/userfiles/files/47122958148.pdfIn PDF document text
    • https://washlounge.in/ckfinder/userfiles/files/59932069338.pdfIn PDF document text
    • http://ipea.kr/userData/board/file/89338903259.pdfIn PDF document text
    • https://motoquadro.de/userfiles/file/51965135563.pdfIn PDF document text
    • https://hobbes-group.com/upload/files/wawofi.pdfIn PDF document text
    • http://ge-mak.com/files/35302681664.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=gsm+based+automatic+irrigation+systemPDF 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_off0000cc58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC58 11060 bytes
SHA-256: 06d87d5d0c56da0e9de8e32be297729c3062ef7d5fce0e6b1f350efd00fccc28
font_01_sfnt_off0000e5f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5F4 17444 bytes
SHA-256: 3fb05dd35c849aa64da83bf34280baeb3abe3a0da1a7920633011446d7d1035f
font_02_sfnt_off00011267.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11267 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1