Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf4c18e9f8edf885…

MALICIOUS

PDF

71.9 KB Created: 2021-09-05 05:32:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 2e189e990ead78ed79f2cbb1b15bcb0e SHA-1: 768cfafcac3633d1dc7f261fe5673e75582e9c26 SHA-256: cf4c18e9f8edf885afab0ec312c6d234986bbf88622d58777b8a61b113ab5a54
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it functions as a link farm. It contains numerous external URLs, some hosted on compromised WordPress sites, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://queure.ru/uplcv?utm_term=ndvi+values+interpretation+pdf PDF link annotation
    • https://daaeportrett.no/upload/file/75689652703.pdfIn PDF document text
    • http://eurekaelearning.com/upload/news/file/daxixakonim.pdfIn PDF document text
    • https://073741256.com/uploads/files/202108311515471412.pdfIn PDF document text
    • https://bokaichenyu.com/upload/files/92399134724.pdfIn PDF document text
    • https://torgradio.ru/new/files/file/93284316367.pdfIn PDF document text
    • http://mastrodibaglio.it/userfiles/files/59255428438.pdfIn PDF document text
    • http://blackivy.pl/userfiles/file/bewasamal.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/ulno4c020skn96sf77sf7l4bqr/xinipax.pdfIn PDF document text
    • http://shophouse.info/images/files/buvaganad.pdfIn PDF document text
    • http://constantcontinuity.com/membership/data//files/bojidik.pdfIn PDF document text
    • http://pokorny-podlahy.cz/UserFiles/File/ketijuwuduvanogobuz.pdfIn PDF document text
    • http://perfekttorun.pl/pliki/xofudigugobarekiwewulore.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c7870cc986ec63f75af169220e013b1b/42064822228.pdfIn PDF document text
    • http://campfirewtx.org/userfiles/file/63069827669.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/62c553185cbf9532728992b8ba6c9764/66211108412.pdfIn PDF document text
    • http://vinmexindia.com/uploads/4003929307.pdfIn PDF document text
    • https://rpdev.org/ckfinder/userfiles/files/14050033816.pdfIn PDF document text
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/4a6fc79f7b12969f0b50f2827a9d2ea7/fobugonelok.pdfIn PDF document text
    • https://pasarantogel2.com/contents//files/wudufiti.pdfIn PDF document text
    • http://copy2d.com/ftp/image/file/70751960767.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094c18b33b70---52423422096.pdfIn PDF document text
    • https://tosto.cl/ckfinder/userfiles/files/79354103315.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a33c99db4eb---46845657290.pdfIn PDF document text
    • http://dental1970.com/clients/5/52/52cfbc2c58cc98a1938bca6351e90795/File/fepezibagovugiz.pdfIn PDF document text
    • 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_off0000bb2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB2D 14952 bytes
SHA-256: 848403b84fbcd386407aed7b651280e288b89b405938820ce293c48646f08440
font_01_sfnt_off0000e13e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE13E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f955.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF955 10632 bytes
SHA-256: cc5ff08efec4e07bfb4a009f2ddb921364ddec13678740df28d7333d0e5858cf