Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a8308c9bdb90e50…

MALICIOUS

PDF

113.8 KB Created: 2021-07-22 22:42:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 6f4035e959e241220f5a41452a8f232f SHA-1: d01b48bd1bb08736a8d628bd7b649b2d5ed5ee1f SHA-256: 1a8308c9bdb90e50bffbbe4f9f19ff52f39e5de6e53191d6ad98f256101b4893
132 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV with a signature indicating a phishing trojan. Static analysis revealed embedded JavaScript and a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to redirect users to malicious content. The presence of PDF_JS and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.4111

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://hoondb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608559f83cd65---57301986942.pdf In PDF document text
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/160848009e35f6---80137406066.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/baa9aefdea447f74d38aacce79f718f6/pejokiluwofabefubax.pdfIn PDF document text
    • http://sashtraayurveda.com/ckfinder/userfiles/files/zusapexoketoj.pdfIn PDF document text
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/ira1up04126num9ts1028a98k6/sujazutozunotafiloxilabaw.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/ddt6dp9gil614a8t1mjd62rqmf/lewiliketufukosadem.pdfIn PDF document text
    • http://movitecnic.com/ressource/site-image/files/58473584692.pdfIn PDF document text
    • http://k-ookuma.com/js/upload/files/62162084047.pdfIn PDF document text
    • http://czdashan.cn/uploadfile/file/2021043010282273499.pdfIn PDF document text
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ccd0773d1da---75877813464.pdfIn PDF document text
    • https://takeorders.online/wp-content/plugins/super-forms/uploads/php/files/g3a5fheticncs34i4iaitslokk/zotutexosilivata.pdfIn PDF document text
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/ceba3c68be1790ffade76c52f3b30cf3/79144729040.pdfIn PDF document text
    • http://wadirumshootingstars.com/userfiles/file///42383250600.pdfIn PDF document text
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/b155c639e1c107f88ed7e9bb467cf241/xewudaxebexuriretemerive.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/ad344eef9aeb20463dcd7870720e636a/75391009910.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a500935f041---70500430847.pdfIn PDF document text
    • http://nprofit.hk/userfiles/90994240277.pdfIn PDF document text
    • http://soportedevida.mx/ckfinder/userfiles/files/sewes.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a56a21a9950---74657419032.pdfIn PDF document text
    • https://dacinsara.ro/fckfiles/file/7468535877.pdfIn PDF document text
    • http://amandamaitland.com/images/file/jakerewol.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aad0880682f---lawilofotadasokigosaturex.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/ec858d9ffa7f05377ffea5f958cc7c4a/84014104336.pdfIn PDF document text
    • https://imaggu.com/ci/userfiles/files/80868592037.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=the+1st+punic+warPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001769f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1769F 10508 bytes
SHA-256: cb1a466b194482e6902e5c5344ba56620fe12cc7317ff744b0422a3f00f921a9
font_01_sfnt_off00018ea0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18EA0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1