Malicious PDF — malware analysis report

Static analysis result for SHA-256 18cad0808ef0b745…

MALICIOUS

PDF

82.8 KB Created: 2021-08-06 17:58:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: ed087ef68926865528003f43e566013d SHA-1: b3735d5d4413c72e66f002e7fa0b10e7542ba09f SHA-256: 18cad0808ef0b7451b355c815ba4b8ff3eb0dc12f5d4e446d2228a46bf495ec1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607071b55a361---54492095096.pdf In PDF document text
    • https://aronabritcan.com/userfiles/file/77848864439.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16073822551311---19316799455.pdfIn PDF document text
    • http://bkht.vn/userfiles/file/96247592823.pdfIn PDF document text
    • http://ural-kip.ru/admin/ckfinder/userfiles/files/24667188063.pdfIn PDF document text
    • http://podwierzba.eu/ckfinder/userfiles/files/90111025331.pdfIn PDF document text
    • https://indirimlipin.com/calisma2/files/uploads/xunib.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac00389912---6441301658.pdfIn PDF document text
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/b0527809ef6d5a6ab40a3eff4b3da997/79622515131.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160967b2ac27a9---fusefifure.pdfIn PDF document text
    • http://xenangheli.vn/public/files/didudogilizixijav.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3cf43ef20---92254301563.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/58604117789.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/68ccc7f9eb779ba2a4498080db818355/negeribijijafe.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/a886f5319457ba3e72adf4a90381a548/jesararix.pdfIn PDF document text
    • http://locke-3c.tw/uploads//files/202108030642538787.pdfIn PDF document text
    • https://profipreklady.cz/www/ckfinder/userfiles/files/11229694788.pdfIn PDF document text
    • http://stroisvias.ru/userfiles/file/80505977361.pdfIn PDF document text
    • http://spc1991.com/ckfinder/userfiles/files/75985416285.pdfIn PDF document text
    • http://immobilieninvestors.de/userfiles/file/kamazimumivog.pdfIn PDF document text
    • http://saikunghouse.hk/userfiles/wepegakutevazimomawadum.pdfIn PDF document text
    • https://telenovella-bg.com/files/75131543138.pdfIn PDF document text
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/a8977aebboitdirpoirk97g2k2/96016810856.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/fikad.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/8047ea9e07f8be7d1fd630821eeaca10/53725081518.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073d604db197---66131843699.pdfIn PDF document text
    • http://graviroz.hu/ckfinder/userfiles/files/79547609094.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=livro+de+biologia+2+ano+ensino+m%C3%A9dio+pdf+2020PDF 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_off0000d8fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8FC 19468 bytes
SHA-256: 8c88501979b32477cfbb62381e8c4de29a485670b20652049bc37777c4d56e36
font_01_sfnt_off000108a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108A7 11300 bytes
SHA-256: bf17971386f3d60b8cb3a67e25f06115217ec5f9ad2998916962aec7574797c2
font_02_sfnt_off0001227a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1227A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1