Malicious PDF — malware analysis report

Static analysis result for SHA-256 768fcba84197ad5c…

MALICIOUS

PDF

87.5 KB Created: 2021-09-17 15:44:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: fdf2c2fff61750553d77873535355740 SHA-1: cd701a269ca56f48d45ca1120ca2b17d79a9bc07 SHA-256: 768fcba84197ad5c70b71e05755553cba8dadc5a32f7737fd54779b3ce2e7eca
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm hosted on compromised CMS upload storage and disposable hosting, with numerous links pointing to potentially malicious PDF files. The document body was unreadable, but the presence of multiple external URIs and the link farm structure strongly suggest a phishing or malicious redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/161421a2333969---tumoxixu.pdf In PDF document text
    • http://thewhitmerlawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/33472540950.pdfIn PDF document text
    • http://multiflex.ru/userfiles/file/43325643175.pdfIn PDF document text
    • http://tonyprins.nl/images/uploads/file/nixagipadidobejetuzot.pdfIn PDF document text
    • http://c2r-auto.com/uploadfiles/file/2021090116050473499.pdfIn PDF document text
    • http://tw-jia.com/uploads/files/202109110616078315.pdfIn PDF document text
    • http://markaz-e-durood.com/EditorImages/file/digoloxevaz.pdfIn PDF document text
    • http://kleinschadenexperte.com/userfiles/file/jurivapofalido.pdfIn PDF document text
    • https://kochitaxirental.com/ckfinder/userfiles/files/4027889712.pdfIn PDF document text
    • http://srcchaika.ru/files/uploads/files/68420481090.pdfIn PDF document text
    • http://msiutilities.biz/documents/55308482802.pdfIn PDF document text
    • http://osstemcardiotec.com/files/fckeditor/file/16374436856142776b7362d.pdfIn PDF document text
    • http://hoachathoanggia.com/userfiles/file/susuv.pdfIn PDF document text
    • https://fluffy-chins.com/images/file/nufaredofuzujataj.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b4cec726c5---sepekitenuvujokifudabeli.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130338590bf3---tolapumod.pdfIn PDF document text
    • http://www.letnifestiwal.pl/ckfinder/userfiles/files/31611519575.pdfIn PDF document text
    • http://szolnokepul.hu/userfiles/file/moluwopaseretud.pdfIn PDF document text
    • http://volareinmongolfiera.it/userfiles/files/7452839070.pdfIn PDF document text
    • http://dorrstrechy.cz/UserFiles/File/sifasegakutafivaxubuxenib.pdfIn PDF document text
    • https://eastoncn.housemember.com/uploads/files/76300362134.pdfIn PDF document text
    • http://entryexpress.online/chapter_images/files/2430310772.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f36da3a1bd---busipe.pdfIn PDF document text
    • http://narnivet.com/userfiles/files/71268943999.pdfIn PDF document text
    • http://zhouzhuanx.com/v15/Upload/file/2021911852464542.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=video+editing+software+kinemaster+for+pcPDF 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_off0000f0ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0ED 17540 bytes
SHA-256: 68acc2509e11562a0c447c6656f06846f12b5b75b13b08a5bab75445c5c15358
font_01_sfnt_off00011e4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E4F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013666.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13666 11064 bytes
SHA-256: 8dca6873b4d4c5d86db42477a8b82e27d3283efac049a1aacd79a105c14a1a52