Malicious PDF — malware analysis report

Static analysis result for SHA-256 966238150f44d489…

MALICIOUS

PDF

85.7 KB Created: 2021-09-10 00:33:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3b9fd8689666d6e1f825f667d497a74d SHA-1: 44757248cb89b9d98c11d885f4a7ee28ce15b759 SHA-256: 966238150f44d489766dd13c35232aaf2aaa9e4173fbec3ae6541cfdebb36a93
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier. It contains numerous links, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to distribute malicious content. While no scripts were explicitly extracted, the PDF structure and heuristic firings indicate it's designed to redirect users to potentially harmful external sites.

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://kiaavcilar.com/upload/ckfinder/files/dezufewigev.pdf In PDF document text
    • http://xn--h1agcmh.com/ckfinder/userfiles/files/81575360431.pdfIn PDF document text
    • https://www.nstoplana.rs/ckfinder/userfiles/files/zewejorapakavekupuravulu.pdfIn PDF document text
    • https://altsovmun.ru/userfiles/file/kidegiwuvesevizerefuda.pdfIn PDF document text
    • http://logistra.fr/ressource/site-image/files/xosuw.pdfIn PDF document text
    • http://rsst77.ru/upload/files/67686190702.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613261c1c8663---35519264202.pdfIn PDF document text
    • http://jaluzipro.ru/public/userfiles/file/46343933727.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16135961a2efd9---337569473.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/161318cf495a90---73276874141.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/fakugaxoso.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161375190d7d07---janekanu.pdfIn PDF document text
    • http://epilia.com/upload/FCKEditorfile/84785173749.pdfIn PDF document text
    • http://tsg-vaganovskoe.ru/ckfinder/userfiles/files/gobazumu.pdfIn PDF document text
    • http://6nergy.fr/6nergy/sites/default/user/file/56282640072.pdfIn PDF document text
    • http://annabarons.com/files/files/10412292044.pdfIn PDF document text
    • http://lovelyspa.net/ckfinder/userfiles/files/53160311056.pdfIn PDF document text
    • http://timebymtm.com/upload/files/zovowudakimaweki.pdfIn PDF document text
    • https://bengalroys.com/ckfinder/userfiles/files/199161622.pdfIn PDF document text
    • https://autopsrus.com/ckfinder/userfiles/files/mogudiwa.pdfIn PDF document text
    • https://bohemiamaestro.com/webpagebuilder/ckfinder/userfiles/files/65832867150.pdfIn PDF document text
    • http://pro-customer.de/userfiles/file/lijofumokujatikazegen.pdfIn PDF document text
    • https://kenkochaya.com/user_data/ckfinder/files/kufalaxazixaxazaxepitokif.pdfIn PDF document text
    • http://ecohost.ru/pics/images/file/dazoripizikokizukimu.pdfIn PDF document text
    • http://hanasushipickup.com/uploads/files/pelewokodalalulegeralen.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=doctor+who+praxeusPDF 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_off0000ed94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED94 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000105ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105AB 10516 bytes
SHA-256: 99ae50f96895cd50f73233527a3ca61f37879b5aa777836b1006ac4f7a2f2ca6
font_02_sfnt_off00011dde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DDE 16684 bytes
SHA-256: 24ba24bff2dac23ec893afcf6dd1f9621dd962323350ce3d52661af9fb51d161