Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb4ac7efdd99e334…

MALICIOUS

PDF

70.9 KB Created: 2021-09-30 11:57:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: a2eec658e2e8143ffb4fbafd23bd3b84 SHA-1: 8fd6744a6f885512eebe367902a67bb4fa3b9ab6 SHA-256: cb4ac7efdd99e3349c5e3140ae4357ba2769a8c3d1c00df594d37b405a28d3a4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to link farms or disposable hosting, suggesting an attempt to obscure the true destination or distribute a large number of files. The `PDF_SEO_DISPOSABLE_LINK_FARM` heuristic further supports this, indicating a strategy of creating many links on potentially untrusted domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://networkinglikepro.com/ckfinder/userfiles/files/sujaxaxib.pdf In PDF document text
    • https://mokshadhamnepal.org/userfiles/files/mepenazisenidaf.pdfIn PDF document text
    • http://andersonlawdecorah.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/94819380702.pdfIn PDF document text
    • http://dobrejaja.com/Upload/file/deneju.pdfIn PDF document text
    • https://frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/surazeneputum.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/52104326501.pdfIn PDF document text
    • http://pfmconsulting.org/survey/userfiles/files/javidolukakajujavonibuw.pdfIn PDF document text
    • https://nothingbutsafetyglasses.com/userfiles/file/4373842666.pdfIn PDF document text
    • http://thaimassageboy.com/ckfinder/userfiles/files/puderelefekaworewaro.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c7301ba21f---70935962551.pdfIn PDF document text
    • https://ctyhoanongangiang.com/userfiles/file/43850916971.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/file/13587552483.pdfIn PDF document text
    • http://insuralead.com/userfiles/file/rinafapalokimet.pdfIn PDF document text
    • http://elrey-uslugi.ru/media/file/13513871206.pdfIn PDF document text
    • http://kerama.altrodesign.eu/ckfinder/userfiles/files/78434064153.pdfIn PDF document text
    • http://cesarrodarte.com/userfiles/file/zirewilunozefiloropot.pdfIn PDF document text
    • http://studiolegalebisantis.it/userfiles/files/godamawadurejejajizefuvi.pdfIn PDF document text
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/jawibagevoguwitej.pdfIn PDF document text
    • http://joyandwowbook.com/upload/file/dorojojepe.pdfIn PDF document text
    • http://mazraeir.com/images/upload/files/seduremivosexadominabuv.pdfIn PDF document text
    • http://holland-ex.com/images/blog/file/16314603564.pdfIn PDF document text
    • http://gzcaifeilai.com/ckfinder/userfiles/files/202109261211003547.pdfIn PDF document text
    • http://rockhousemethod.com/ckfinder/userfiles/files/27512798655.pdfIn PDF document text
    • http://ristoranteyuri2.com/userfiles/file/20027923882.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=why+by+simon+sinek+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_off0000b1da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1DA 10696 bytes
SHA-256: 4f7045b654519070b355dd2715fc47b954edc92cf1ad92c13e5a38dd4c8a3b6b
font_01_sfnt_off0000c9f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9F6 17424 bytes
SHA-256: 3427765131578a22fe6b9a3bc6f80c3e70d3c5ba654d259852fa2f5bf814ae0c
font_02_sfnt_off0000f66c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF66C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1