Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6b37fde8458bf23…

MALICIOUS

PDF

73.5 KB Created: 2021-09-17 12:03:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 34f31a9cf818cab403ede3a40965c038 SHA-1: 9c1cfaeba5682b862d1b3cb7a19fd363e372e401 SHA-256: a6b37fde8458bf23aa941ac318cadae198e63d3623541dda36b3b3245f3b898e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous links to external websites, many of which are hosted on compromised CMS uploads or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this phishing and redirection attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://huntic.ru/uplcv?utm_term=apple+phone+bd+price PDF link annotation
    • https://eastmangroup.org/ckfinder/userfiles/files/wiwefoxowupu.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/9b128fc00a16f088927d01ce46ac13ed/81292494424.pdfIn PDF document text
    • http://vhshf.de/File/janoviziko.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/d9eca6765bfd5a4022e8407b4fa87298/74777949849.pdfIn PDF document text
    • http://yilip.net/userData/board/file/kitutivejobivok.pdfIn PDF document text
    • http://andrenickels.de/ckfinder/userfiles/files/2729705377.pdfIn PDF document text
    • http://mynotary.ca/sites/all/sites/mynotary.ca/files/12761032720.pdfIn PDF document text
    • https://piataafacerilor.ro/app/webroot/files/userfiles/files/4073812381.pdfIn PDF document text
    • https://dogathermalhotel.com/resimler/files/damidozo.pdfIn PDF document text
    • http://boki.hu/editor_up/34446224421.pdfIn PDF document text
    • http://ewtch.com/upload/files/sopujoxuze.pdfIn PDF document text
    • https://sherwoodchamber.org/ckfinder/userfiles/files/1355984252.pdfIn PDF document text
    • https://digireg.com/upload/56840757850.pdfIn PDF document text
    • http://wsospice.org/uploads/userfiles/file/file/fanewaxupexuzabowojibu.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/47546591019.pdfIn PDF document text
    • http://zoltysnieg.pl/pliki_wyswig/files/57004068510.pdfIn PDF document text
    • http://imdad-egypt.com/userfiles/file/90708859370.pdfIn PDF document text
    • http://sieuthibds.net/images/files/resadutaguma.pdfIn PDF document text
    • http://windowsplusllc.com/ckfinder/userfiles/files/lidazikusixebula.pdfIn PDF document text
    • http://dintainoodle.com/uploads/files/45274832399.pdfIn PDF document text
    • https://eurotig.ro/file/99916545903.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/13097ffc1a4d4ed6c91ec64fa2bd7854/xumen.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/3ff2574fe2c6271ed38bccc01e447058/vuforujajekisigugovotuzer.pdfIn PDF document text
    • https://remoteyourstaff.com/calisma2/files/uploads/likukulekol.pdfIn PDF document text
    • https://www.clinicaepilepsia.cl/ckfinder/userfiles/files/1116323824.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_off0000bf1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF1B 10304 bytes
SHA-256: 47e9556295f5efb751d2f972d53dd097c819c6359809b199e8064216dc795f63
font_01_sfnt_off0000d5eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5EB 16920 bytes
SHA-256: b405fbf99132f0fbb76460c6ae44b70ac106fa5f0ff7e4dcba0e415d4e00d7f7
font_02_sfnt_off00010045.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10045 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1