Malicious PDF — malware analysis report

Static analysis result for SHA-256 af593fab61264bc8…

MALICIOUS

PDF

160.8 KB Created: 2021-09-11 03:59:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-23
MD5: 2e353f8a9edaf01f198fc2be648a4cf0 SHA-1: 90088c5b4c68a35dd29950b129f81339f547f9ba SHA-256: af593fab61264bc8ed1e64228fca0e27423685a567faa8ca1c594b69df8175d3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9871

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://jr.ac.th/ckfinder/userfiles/files/losewatujotunezer.pdf In PDF document text
    • http://hydrem.ru/images/file/fufusebixizejujera.pdfIn PDF document text
    • https://rimi.sk/userfiles/file/rejagukawu.pdfIn PDF document text
    • http://matraholding.hu/images/userfiles/files/90943473534.pdfIn PDF document text
    • http://iphysiology.ru/upload/buvofelogaribetijil.pdfIn PDF document text
    • http://ceramicaartisticamarsalese.it/userfiles/files/78676858740.pdfIn PDF document text
    • http://insightonafrica.in/userfiles/file/12363054154.pdfIn PDF document text
    • http://compagniaviaggi.gattinonimondodivacanze.it/themes/userfiles/files/modedumejifusev.pdfIn PDF document text
    • http://cyklo-sport-servis.cz/UserFiles/File/46957332276.pdfIn PDF document text
    • http://chinawin-consult.com/userfiles/54502356563.pdfIn PDF document text
    • https://etest.vn/app/webroot/uploads/files/fijun.pdfIn PDF document text
    • http://www.sandzthabapanel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16138719a04e56---gukidegebajogefuramureses.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131578bc2d79---wutifufodexijunamu.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/b7b27ec01e79795969f045e14c415859/60483904431.pdfIn PDF document text
    • http://trunglam.vn/uploads/userfiles/file/65135780432.pdfIn PDF document text
    • http://futurepoolandspa.com/ckfinder/userfiles/files/siladilugab.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613274eb043f2---volaxujanali.pdfIn PDF document text
    • http://omni-links-europe.com/images/blog/file/wamezokawumeperabawoxodu.pdfIn PDF document text
    • http://vikingpaint.com/user_file/file/10475708450.pdfIn PDF document text
    • http://indianspringhomes.com/userfiles/files/8940834052.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/161354a56d9617---mawogoninisiwegituxasebe.pdfIn PDF document text
    • http://cross-winds.in/upload/contents/images/images/xafemibimo.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613739ee8a62c---79842785325.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137c6d35f335---12724880439.pdfIn PDF document text
    • https://clinicamanila.com/ckfinder/userfiles/files/12194801122.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=music+ui+designPDF link annotation
    • http://mustang.tom.ru/jsplugins/ckfinder/userfiles/files/60796183410.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_off0002142c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2142C 19492 bytes
SHA-256: af5c4dfc4ea6670f90089fc859fa7e5910166aa98d77fa4d6d7947cb634460bc
font_01_sfnt_off0002467f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2467F 10112 bytes
SHA-256: f99e1c192614e4482ef2c35e6b1e86696f8c705fd55a4b95c8ce7aee053ac264
font_02_sfnt_off00025cee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x25CEE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1