Malicious PDF — malware analysis report

Static analysis result for SHA-256 1971d738c1a612bc…

MALICIOUS

PDF

99.4 KB Created: 2021-07-27 17:11:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 4122079c7a3977a57f48f95f4a10f200 SHA-1: d316640c76ec9a8c9c2b47878e6678cc630cb387 SHA-256: 1971d738c1a612bcbb71f74acac518509c3034a7e21f45e3e08cca2515b455cf
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating it likely exploits a vulnerability or contains malicious content. The document functions as a link farm, with numerous embedded URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to manipulate search engine rankings or distribute further payloads. No scripts were extracted, but the presence of multiple external links and the nature of the hosting indicate a phishing or content distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://qctc.vn/upload/files/gazakeberejizepit.pdf In PDF document text
    • https://walnutcreekguide.com/wysiwygfiles/file/kisimu.pdfIn PDF document text
    • http://efuturesthai.com/uploads/files/93201573717.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/9632431485f2e1459f18a01355dade74/73774138171.pdfIn PDF document text
    • http://kondicionery-dolgoprudny.ru/upload_picture/file/1992125122.pdfIn PDF document text
    • http://maxbrio.kr/files/files/68001867551.pdfIn PDF document text
    • http://alibabashipping.com/userfiles/file/xelumasuvaletedotuja.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/e003874d6edf9d00a2f754a6034ccff9/memox.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c28fba0a719---foxozajedafujisomitep.pdfIn PDF document text
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/u9vbidjjcanefq6o2f56q2k7pm/4873776301.pdfIn PDF document text
    • https://stratasphere.online/userfiles/file/ruwewomomoleme.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609dcd3b13d03---bisatesudenobiwafera.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097bb238ca77---lujeguji.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608c0ef2b4792---77074204828.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/ad4ff7035f7ef4699fa900c8dc6e9625/lobifofulalokix.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b376bf704cd---jenowalidaj.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160b445744b99d---xewajavokidowujazo.pdfIn PDF document text
    • http://sattosushi.com/uploads/files/febutajuwegarogun.pdfIn PDF document text
    • http://hanasushimenifee.com/uploads/files/dosetalazi.pdfIn PDF document text
    • http://banghetretunhien.com/media/ftp/file/tolumejamujegin.pdfIn PDF document text
    • http://turatabor.hu/media/96374038315.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/96aeefc467d754ddd44cc90fbc6ec6f0/76509134704.pdfIn PDF document text
    • http://ideviceplus.nl/app/webroot/files/userfiles/files/xibalekova.pdfIn PDF document text
    • http://toshiteriyakiburien.com/uploads/files/buzaw.pdfIn PDF document text
    • https://atcotourismtravel.com/userfiles/file/12953064771.pdfIn PDF document text
    • http://aggengr.com/uploads/CMS/file/falida.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=cuaderno+de+ejercicios+de+letra+cursiva+pdfPDF 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_off00011d55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D55 19024 bytes
SHA-256: 3b60cba6beddcb827602acd39629cd5b5fec845a9be025db8834124e69daab9f
font_01_sfnt_off00014d6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D6D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016584.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16584 10940 bytes
SHA-256: fcade0cc82e7bcd68e59f24c27e7fb8553fab72dcda15695ae108b77cb0665bd