Malicious PDF — malware analysis report

Static analysis result for SHA-256 c51acadc511fa8cb…

MALICIOUS

PDF

77.9 KB Created: 2021-09-01 11:30:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: a89a4b917f1ab2f3a2df15cd93329123 SHA-1: 8c1a93cdbadf27678f9d6c32e23b969c0fa4cbe5 SHA-256: c51acadc511fa8cb9c8c4facd022572bd0ad59340a92dc93359c4c6168e90c01
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous embedded URLs that point to compromised WordPress sites. These links likely serve as redirects to phishing pages or malware download sites, indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160bd7983e1ac6---66564440103.pdf In PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b6fba45ae1d---sedafativovede.pdfIn PDF document text
    • https://pointvirgule.ca/upload/editor/file/teximilo.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c15e6f4f763---41170959393.pdfIn PDF document text
    • https://globaltranslation.com/demo/global_translation/beta/userfiles/files/datixosiferimejizutu.pdfIn PDF document text
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/333ad2e95a75f16baac7221b1a735fad/94519912563.pdfIn PDF document text
    • https://biovuspharma.net/userfiles/files/sapepanuwurun.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608231411c003---53434609077.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/6fdb8126df89e480425a3e9f1f437cc2/selezewaxuvusofiru.pdfIn PDF document text
    • http://bpsstudio.hu/uploads/32314216507.pdfIn PDF document text
    • http://studio-orlandini.com/userfiles/files/55617532193.pdfIn PDF document text
    • https://greyquotient.com/wp-content/plugins/super-forms/uploads/php/files/9b14c872bd0da90f7d277d4d75429847/46686200730.pdfIn PDF document text
    • http://studiosiciliani.eu/userfiles/files/fezekawezifaf.pdfIn PDF document text
    • http://yuhenganquan.com/userfiles/file/20210812235911_1029298783.pdfIn PDF document text
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/buvi814jk4s9h0ner6gvo85m03/15778170339.pdfIn PDF document text
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/q0j0o1nn31t1fseofbv2ao6fh2/fiwofefubosujala.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607da7795fa54---80295733213.pdfIn PDF document text
    • https://www.nexidia.it/wp-content/plugins/super-forms/uploads/php/files/5de4c426f663329a8c55958e2ca5606a/50790602546.pdfIn PDF document text
    • https://saatyapi.com/upload/ckfinder/files/lomamuke.pdfIn PDF document text
    • http://beloezoloto.ru/userfiles/file/givokijovezoribev.pdfIn PDF document text
    • http://kondicionery-vidnoe.ru/upload_picture/file/jixemirutisunasosa.pdfIn PDF document text
    • https://forcechicago.com/wp-content/plugins/super-forms/uploads/php/files/b95e124741225ce963687d3b1ec5278b/31801621082.pdfIn PDF document text
    • https://perfecthospitals.com/ckfinder/userfiles/files/gamamevorirowefaxajip.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160dfdff4ec109---77032641009.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=ham+radio+technician+test+questions+and+answersPDF 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_off0000ca37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA37 18068 bytes
SHA-256: 0663d251cdb53e4676b25c5edae27d83aa052367c0d96f35f62c83f9637b257f
font_01_sfnt_off0000f8fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011113.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11113 10912 bytes
SHA-256: 4adaaebe842c3a549151bcbb3fc022e386d2c7a79327c3458cb4fa82620c12d2