Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a948ae67ac6f36e…

MALICIOUS

PDF

81.5 KB Created: 2021-06-25 21:31:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: c934076d2aabe239e2b21e95bd8b6e40 SHA-1: d74908cc188b39f31de1459c9c72a06dd2f3019c SHA-256: 5a948ae67ac6f36e7f76fb15b602868e4da18ad72ae760dc34dbd4f354ce2792
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to phishing or malware sites. The PDF structure itself does not contain readable content, but the embedded URLs and heuristic firings strongly suggest a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://garglob.ru/uplcv?utm_term=determine+whether+the+three+points+are+collinear PDF link annotation
    • http://predit.ru/admin/ckfinder/userfiles/files/41606281275.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/0q03ubvl7amnkk9hbeaip8d6de/mopegimoveluseseduse.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/16091cabd57087---libagipeniva.pdfIn PDF document text
    • https://cabsfromheathrow.com/userfiles/file/71785258925.pdfIn PDF document text
    • http://libron.pl/fckupload/assets/file/wemajogunap.pdfIn PDF document text
    • http://china-zub.ru/userfiles/file/72472371428.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf90da0fc46---bozubedoxesek.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/52ed0a6f12f6947fa7e40b2777c1c734/43845342273.pdfIn PDF document text
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/gcb9mchofc6ni0cdpc75tnfqt1/watujisuse.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/matekerilokudo.pdfIn PDF document text
    • http://krevue.cz/UserFiles/File/38795190296.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d1cb70c9fb---dapokovenemuwejomijarek.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/bec2aefbb969afe323a6bbf378dedc2b/50446599940.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/a451a79a22c1ecee9a2d75f2c16dc895/juduravub.pdfIn PDF document text
    • https://psiakocky-potisk.cz/webpagebuilder/ckfinder/userfiles/files/17752317019.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/ac29ef55db8c6a98f36ab737876a9c49/62556844166.pdfIn PDF document text
    • http://arc-en-cielproduce.com/ckfinder/userfiles/files/gidijoj.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8e8b6ac616---bekabufosemura.pdfIn PDF document text
    • http://arcos-eff.it/userfiles/files/dutegegonevemegixikibi.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1608e6dc88fef6---gepex.pdfIn PDF document text
    • https://tarzminder.com/resimler/files/98645230319.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/t1lbecrs224rfdep51v7e8ro7f/98563456552.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/e1c62fa8ef7f5d61f8667127a5a58569/gevuwepod.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b92f6e863d7---4084555637.pdfIn PDF document text
    • https://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608e786e1a805---makapekidapisa.pdfIn PDF document text
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/dejuxekarix.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_off0000d8a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8A7 17648 bytes
SHA-256: 0cd8d450e40a40ce6c7a7f8109f8658977ec016fe1c5ff6c7c111abf06256396
font_01_sfnt_off00010791.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10791 10724 bytes
SHA-256: bdb06487a86b9f8678d19bb1a3b071029fed73a593984289f9f2cb04331e6d04
font_02_sfnt_off00012013.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12013 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1