Malicious PDF — malware analysis report

Static analysis result for SHA-256 e71b42ca0268aef4…

MALICIOUS

PDF

67.3 KB Created: 2021-06-17 20:00:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: f5f8e0953c9c0d6a90d484da14c6321a SHA-1: 71efb6858d53376b9f0d8c5df4a852e3762db461 SHA-256: e71b42ca0268aef47a178f652ac89fc61133eabf7fe3ae71a053261fb0458f86
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress upload sites and disposable hosting domains. The presence of embedded URLs and the nature of the link farm suggest an attempt to distribute phishing content or further malware payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://dollarplus98.com/images/upload/files/fobeber.pdf In PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160763c898d2e6---mivulusoletonegezoravase.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/3a9e4694ddde989a2e7f947b28b7f012/48960897088.pdfIn PDF document text
    • https://varbackaforskola.se/ckfinder/userfiles/files/kosedizotunela.pdfIn PDF document text
    • http://yakutiaprime.ru/SITE/files/editor/file/melemekalimugixapitek.pdfIn PDF document text
    • https://ancoraeducacion.com/images/mepasalelanikotoxud.pdfIn PDF document text
    • http://chroscina.com/userfiles/file/lugutamepulupana.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/160744a7333554---luvazi.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160831efcaf563---dofilenazijasijuniw.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1608d9f8b56565---88333523920.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/58014455599.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607b26201b0d5---42931946324.pdfIn PDF document text
    • http://begemot-rus.com/uploadfiles/file/2021060806083773499.pdfIn PDF document text
    • http://www.liveartsaskatchewan.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090cb3dd0505---32762662489.pdfIn PDF document text
    • http://mlsconsulting.net/cms/files/File/meralusugowasojikasuxiveg.pdfIn PDF document text
    • http://cissi.it/userfiles/files/romelelevunikomirevubad.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c1c03b5eda---37683474527.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=big+bear+gay+daddyPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cadf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCADF 5076 bytes
SHA-256: b6d9e064fcbe74f494e1c51e45a89b3df54bf1a290948391d5dc53567f5b8488
font_01_sfnt_off0000dc39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC39 10516 bytes
SHA-256: 4253cb02f880929861f599210f962aec4ca0a9d81ec3dfa95596da262d5f0260