Malicious PDF — malware analysis report

Static analysis result for SHA-256 c98033d83fa7f6b5…

MALICIOUS

PDF

87.0 KB Created: 2021-07-16 16:13:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: ddc3d44c61d265e27d0c680ba0995b1f SHA-1: 6deec3af5f66f3b84b576991cd9f6da51212d197 SHA-256: c98033d83fa7f6b597d540a0e4f5a6a6d1f5e28894fd54dde4f0c5d02eed8b92
156 Risk Score

Malware Insights

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

The ML classifier and ClamAV detection strongly indicate this PDF is malicious. It contains numerous links pointing to compromised WordPress sites and other domains, suggesting it functions as a link farm to distribute further malicious content or phish users. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a pattern of using disposable hosting for link distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://ippon.lv/uploads/File/nesagulewagisuzowutar.pdf In PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/61faf49e3e1ffc4657a7da790bf48061/37231715262.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/1e4357a0b05184ccd9cb8052e4d304aa/13593298001.pdfIn PDF document text
    • http://ehs1958.org/clients/73155/File/dopolulaxam.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfcfcedb620---jalokixagenibuvisatim.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160bd5e214183b---79881123352.pdfIn PDF document text
    • http://haai.org/upload/file/71545112359.pdfIn PDF document text
    • https://cbconsulting112.ca/userfiles/files/patafojepakuleva.pdfIn PDF document text
    • https://driftwoodcc.com/userfiles/files/80896384184.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc5a57a22b---delufituf.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aaf6529e2e0---walijoromepif.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/iesegtldhd53nnrmkcdlgjjhih/wuzepoxajagavomen.pdfIn PDF document text
    • http://originalcheck.it/public/img_admin/file///13727893405.pdfIn PDF document text
    • https://www.propertyfilevault.com/wp-content/plugins/super-forms/uploads/php/files/0fe9389668cbdaf0dacb3bfaea18ab8b/ritelatezuj.pdfIn PDF document text
    • https://clinicscrm.com/img/files/fuxudu.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/go3gtsirus541tlcvbmhsgtoov/1752835845.pdfIn PDF document text
    • http://cp-tournament.org/ckfinder/userfiles/files/bamufefunivefitan.pdfIn PDF document text
    • https://balajitutorial.com/admin/userfiles/file/17385540313.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/28feac5c8afe6f9ee356f20591c0d3a9/39140219633.pdfIn PDF document text
    • http://studioingegneriavaragnolo.com/userfiles/files/fubogabo.pdfIn PDF document text
    • https://remoteworkerclub.com/wp-content/plugins/super-forms/uploads/php/files/84f1ab459a26afe648bff3f1746e881d/34096862913.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609eb2c31d7f5---67986244878.pdfIn PDF document text
    • http://malbreil.com/userfiles/file/58432529658.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607b570920d31---44453998073.pdfIn PDF document text
    • http://unesco-mediain.cz/fckfiles/file/13406500483.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=boys+names+that+start+with+roPDF 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_off0000f286.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF286 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010a9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A9D 10580 bytes
SHA-256: e0592b1fa979cc674fccdb9d4314b2e7a8721c114f408f5946f2d597a2f02c83
font_02_sfnt_off000122ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122AD 16860 bytes
SHA-256: 4816c6feb5e19b2e5799ce39382570a034e7af544725015c883c8a3ec2c1877e