Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8145e7ccff18728…

MALICIOUS

PDF

81.5 KB Created: 2021-09-21 06:24:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 809a04ea1b47b8a0a983d38cb73529bd SHA-1: ff7ab0717f8ad3b20580dca79aa03ba1477d1a80 SHA-256: f8145e7ccff187283f94a8ee01de4de03fd096997e2391616b5385d417533dff
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URIs and link farm heuristics indicates an attempt to lead users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 http://ivankrivanek.com/userfiles/file/1298812318.pdf In PDF document text
    • http://ncfc.com.tr/ckfinder/userfiles/files/48807004676.pdfIn PDF document text
    • http://dar-tom.pl/userfiles/file/zujuximanunitag.pdfIn PDF document text
    • https://zegaoyun.com/calisma2/files/uploads/40890376735.pdfIn PDF document text
    • https://vasantviharproperties.com/userfiles/file/lagaraxabe.pdfIn PDF document text
    • http://ucinnovation.ru/admin/ckfinder/userfiles/files/55964068900.pdfIn PDF document text
    • http://xuanfe.com/uploads/FCKeditor/file/vuvopiz.pdfIn PDF document text
    • http://knowleangling.co.uk/ckfinder/userfiles/files/68734712501.pdfIn PDF document text
    • http://aexpress.lv/index/images/up/file/91110195733.pdfIn PDF document text
    • http://grandp.ru/userfiles/file/jagezoxi.pdfIn PDF document text
    • http://ned.ru/uploads/files/pusadi.pdfIn PDF document text
    • http://pascalparrot.com/uploads/assets/file/3582684793.pdfIn PDF document text
    • https://hunghiephuylog.com/upload/files/27588185641.pdfIn PDF document text
    • https://cashcruis.ru/wp-content/plugins/super-forms/uploads/php/files/738d904094702183a279e21bc69b7c43/gobazisusonuwovaripupine.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/161462e99f0fc7---56335962615.pdfIn PDF document text
    • http://surestegc.org/documentos/file/46893607096.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/lugaragafegiwusajetuxan.pdfIn PDF document text
    • http://asckhn.com/acskhn/userfiles/file/39229959104.pdfIn PDF document text
    • https://hamzakocakoglu.com/userfiles/file/2966253895.pdfIn PDF document text
    • http://vxclouds.com/userfiles/file/segotu.pdfIn PDF document text
    • http://tourhong.com/FileData/ckfinder/files/20210904_14B1930F766F8A3C.pdfIn PDF document text
    • https://www.playitdirect.ca/ckfinder/uploadfiles/files/94543004286.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/205b595c75n0lv1a3deod4fr6h/56799289093.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/16138799a9943a---99454801003.pdfIn PDF document text
    • https://gamedunyasi.com/calisma2/files/uploads/witosotanat.pdfIn PDF document text
    • http://giftboxvietthuy.com/upload/ck/files/lidopufegijojot.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=instagram+auto+liker+tool+apk+downloadPDF 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_off0000d87a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD87A 17848 bytes
SHA-256: 0893ce490a61805bbf544d20ac12971ee9608c8d04912468c4f9d2627eeb5d0b
font_01_sfnt_off000106e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011efb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EFB 10964 bytes
SHA-256: 05cea7a220dd7cfed471f51346d35d7d1b8c64b15432a94f87c9630804e5fd94