Malicious PDF — malware analysis report

Static analysis result for SHA-256 f11e37badf99e57f…

MALICIOUS

PDF

71.6 KB Created: 2021-09-28 12:43:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1c7f757415e41006792323109e565f2e SHA-1: 637b05cb7a207e2d1477a55514e31700e21cf7ca SHA-256: f11e37badf99e57fda68db51db0868444a37bca238b3d9e6fcec96f6a5cf5d0e
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised or disposable domains, suggesting a phishing or malware distribution scheme. The presence of a link farm on disposable hosting and a link to a compromised WordPress upload storage further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://krisoc.ru/uplcv?utm_term=real+time+screen+translator+android PDF link annotation
    • http://immobilier-valence-agen.com/userfiles/file/76858022814.pdfIn PDF document text
    • http://saydersan.com/firma/files/xabatokapopupef.pdfIn PDF document text
    • http://osmed.cz/app/webroot/files/files/99799084743.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/gopafekilewale.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/1f670a6f84dcfad430b60cfd595f3ae4/28192877662.pdfIn PDF document text
    • https://pmeds.us/userfiles/file/zuvenenogixetom.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16135957ab2bbc---vovuzoz.pdfIn PDF document text
    • http://apartamentykunickiego.pl/architekci/public/upload/ckfinder/userfiles/files/safovojoxejofedud.pdfIn PDF document text
    • http://erbaytag.com/resimler/files/32381275139.pdfIn PDF document text
    • http://solemarservizi.it/userfiles/files/vuxideren.pdfIn PDF document text
    • https://www.rosebankprimary.co.za/inc/ckfinder/userfiles/files/jijogumazosilipudibas.pdfIn PDF document text
    • https://nbc.com.vn/ckfinder/userfiles/files/xavexopuwefizewoma.pdfIn PDF document text
    • http://gk-eventus.ru/admin/ckfinder/userfiles/files/zitusumutiwalovip.pdfIn PDF document text
    • https://abcoegypt.com/userfiles/files/xujuwagiwowobejas.pdfIn PDF document text
    • https://cartolmania.it/file/vodesesojapivoxegitolejok.pdfIn PDF document text
    • http://drdj.friend-match.com/upload/files/baxikokuxokivos.pdfIn PDF document text
    • http://sriraghavendratemple.com/ckfinder/userfiles/files/6833033670.pdfIn PDF document text
    • http://koopmankennedyfeller.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/39470315230.pdfIn PDF document text
    • http://fpole.ru/sadm_files/vimole.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/60153703044.pdfIn PDF document text
    • http://paneldeconso.com/userfiles/file/difeduzi.pdfIn PDF document text
    • http://reicar.dk/userfiles/file/jofalobu.pdfIn PDF document text
    • https://resicolor.com/upload/files/32883994622.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141161d5902f---85569606179.pdfIn PDF document text
    • http://www.hgbehringer.de/img/files/files/21962115730.pdfIn PDF document text
    • 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_off0000b3df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3DF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cbf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBF6 10576 bytes
SHA-256: 769227b4eb78cdf523c8b5b7df6792afc62b3d8c801d62425a80dfbf510e3138
font_02_sfnt_off0000e40c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE40C 16640 bytes
SHA-256: d0fb0626c31ec8f8cd2794f954be4dfbd821509a7cf69a2f5c577603e0bae233