Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6c4ca4a8b608ff3…

MALICIOUS

PDF

81.8 KB Created: 2021-09-17 22:24:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 125287207b02061dbc1ee3f2fe1f8144 SHA-1: e2dec4502b39daf030f47d68680e7f8399dc0695 SHA-256: f6c4ca4a8b608ff3864e745c60958d55f24a80eebeada79fb9177b867d4bcf3d
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as a link farm, with a high ML score and ClamAV detection indicating malicious intent. The numerous embedded URLs point to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The document body is unreadable, but the presence of many external links strongly indicates a malicious redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://nomylo.ru/uplcv?utm_term=how+do+you+download+fortnite+on+a+tablet PDF link annotation
    • https://bravo-hk.com/userfiles/file/48510394040.pdfIn PDF document text
    • http://a-xian-coat.com/uploads/files/202109091609493897.pdfIn PDF document text
    • https://saglamahsapkutu.com/img/editor/image/file/vizexorudukuw.pdfIn PDF document text
    • http://iucecb.com/files/file/pofug.pdfIn PDF document text
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/2bb6e83dd147e7b6acbae18dface42bf/34562083182.pdfIn PDF document text
    • http://satyavnetworks.com/fck_upload_images/file/rewijosasefijuxema.pdfIn PDF document text
    • http://casavacanzesanvito.eu/userfiles/files/manorezupeda.pdfIn PDF document text
    • http://fulns.com/uploadfile/fckedit/file/1631390675YvpF.pdfIn PDF document text
    • http://dawahcity.com/userfiles/file/rudenosiziged.pdfIn PDF document text
    • https://kolorubursztynu.kolorubursztynu.pl/web/uploads/files/62227535353.pdfIn PDF document text
    • http://sonnenheizung.ch/fckeditor/editor/images/file/84346194263.pdfIn PDF document text
    • http://poltinik.ru/userfiles/file/xaxere.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/1613f3623f1d9d---49609650790.pdfIn PDF document text
    • http://asavn.vn/uploads/userfiles/files/wuzate.pdfIn PDF document text
    • https://cmfnepal.org/userfiles/files/11077200385.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/531a734fddadeeb61608947663f94a35/5346148303.pdfIn PDF document text
    • http://ymjgolf.com/file_media/file_image/file/40309071646.pdfIn PDF document text
    • http://xn--80adpfaaeictf0c6c7i.xn--p1ai/public/file/98210268117.pdfIn PDF document text
    • https://baruipur.org/ckfinder/userfiles/files/fudoxunakotozanosi.pdfIn PDF document text
    • http://preprod.app-nomads.com/ugecam/admin/ckfinder/userfiles/files/65117266752.pdfIn PDF document text
    • http://newshop.jp/archive/file/gavufazobilokalinejateli.pdfIn PDF document text
    • http://fence-alarm.com/userfiles/files/64941403608.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_off0000d9ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f1e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1E5 10608 bytes
SHA-256: 6e9987a5fdf0067362153bc7028d056698775303579c166f5efe31dac3a4eba2
font_02_sfnt_off00010a3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A3F 18160 bytes
SHA-256: 2c7eb0e0f5b0bdc9945ed8a842bdf86f7f984310cb6145c82d2bca107d48abee