Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ae37e1eac28c033…

MALICIOUS

PDF

89.2 KB Created: 2021-09-15 23:00:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: bfc8612bcd0803171e73a6feab906177 SHA-1: 94160dcc2fb6bc1f42065598823b0c171059c71f SHA-256: 4ae37e1eac28c033d9d26cc8a97484727040cb0008c34b13b99ee000114ad4f5
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, indicating it is likely a phishing or malware distribution lure. Numerous heuristics point to the PDF acting as a link farm, directing users to various external domains, many of which are hosted on compromised CMS platforms or disposable hosting. The presence of multiple PDF-specific heuristics and the ML detection strongly suggest an exploit or malicious content embedded within the PDF structure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://bem-sa.com/img/file/lomugutagesupuve.pdf In PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/4p8mn614h19e54nqgkbkcun5c4/wuxozozepimivekinefis.pdfIn PDF document text
    • http://szintai.hu/ckfinder/userfiles/files/jemegakubemogejop.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614195ea8c807---97999664251.pdfIn PDF document text
    • http://compagniaviaggi.gattinonimondodivacanze.it/themes/userfiles/files/jadujisuvuvogom.pdfIn PDF document text
    • http://acecaalcoy.com/userfiles/file/45347992135.pdfIn PDF document text
    • http://bodemveenweiden.nl/bodem-veenweiden-img/misawubavaseguvu.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/1613094488a956---47268820795.pdfIn PDF document text
    • https://tranhtreo.com/images/ckeditor/files/20930707373.pdfIn PDF document text
    • http://sapientgenerator.ru/files/userfiles/files/boxawamonuno.pdfIn PDF document text
    • http://087334211.kad.tw/kads/ckfinder/userfiles/files/69288447815.pdfIn PDF document text
    • http://12shio5.com/contents/files/87398187520.pdfIn PDF document text
    • https://terrebleue.org/userfiles/file/70163162845.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16131d61d1400b---95659159993.pdfIn PDF document text
    • http://metabolizmusonline.hu/images/upload/file/gigubumipimiwikuguxasabif.pdfIn PDF document text
    • http://w-mill.jp/images/file/wezozijawerulugo.pdfIn PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/16138c00b35c25---sowuwutewubop.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/c3bf6a4f06022ce7b243f3f1de6732ab/bifafemomimenowumedujebex.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613b592f70563---21646524608.pdfIn PDF document text
    • http://www.sintsprev-ms.org.br/ckfinder/userfiles/files/92429244644.pdfIn PDF document text
    • http://ppogrimall.com/upload/editor_image/file/jogamosusele.pdfIn PDF document text
    • https://beautyyaurient.com/editor_upload/file/71186769385.pdfIn PDF document text
    • https://hearing-outlet.com/uploads/files/202109021928143848.pdfIn PDF document text
    • https://lmbri.com/WYSIWYGImage/file/meratax.pdfIn PDF document text
    • http://gaziogluenerji.com/images_upload/files/muzixulurudevopefop.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=adrienne+rich+poetry+themesPDF 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_off0000f6d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010ee5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EE5 18288 bytes
SHA-256: 577b92c57978a18d0880db825e50a69e4623a9a968babb039a33d22be11fad7f
font_02_sfnt_off00013e98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E98 10668 bytes
SHA-256: 81bebf0fae75cfdb1dc03b0d089d1437df313c5d52ecfe0829b0199059444728