Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3f5ba612e813da6…

MALICIOUS

PDF

79.4 KB Created: 2021-09-13 04:48:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 478438fc313333f90ef5aa375d196b18 SHA-1: 965e9557af0bb69dd0a84b5b07d630e303910dd6 SHA-256: a3f5ba612e813da607f6ccdd0ec15aff0975d147fc2e6335fd8bffd0f5033859
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm on disposable hosting, indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic and multiple unknown reputation URLs. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were extracted, the structure and heuristics point to a malicious document designed to trick users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://xinchenfast.com/upload/file/29825352363.pdf In PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/161336cd29ba40---porawodo.pdfIn PDF document text
    • https://hitourkorea.com/FileData/ckfinder/files/20210904_BF668398F58A3326.pdfIn PDF document text
    • http://www.mamafoundation.cz/ckfinder/userfiles/files/11077876959.pdfIn PDF document text
    • https://cbdc.co/uploads/ckfinder/userfiles/files/67157408926.pdfIn PDF document text
    • http://hiniceshine.com/upload/65151511786.pdfIn PDF document text
    • http://rosabaum.de/web/editor/files/mefutojituj.pdfIn PDF document text
    • http://skonasystems.com/userfiles/file/80719095316.pdfIn PDF document text
    • https://artgreen.vn/attachment/files/dovibipo.pdfIn PDF document text
    • http://kolaykanal.com/userfiles/files/raruwumilaro.pdfIn PDF document text
    • http://asremajazi.com/uploads/files/zukupinima.pdfIn PDF document text
    • http://sinostandards.net/upload/files/80640589768.pdfIn PDF document text
    • http://idevicesplus.nl/app/webroot/files/userfiles/files/42630309295.pdfIn PDF document text
    • http://poongdung.com/FileData/ckfinder/files/20210901_9F14111A37329237.pdfIn PDF document text
    • https://aradovan.com/userfiles/file/84534585632.pdfIn PDF document text
    • http://women-for-marriage.com/ckfinder/userfiles/files/51639897719.pdfIn PDF document text
    • http://aroma-es.red/yamituki-n/uploads/files/1457823469.pdfIn PDF document text
    • http://celeb.huh.hu/UserFiles/File/35332086505.pdfIn PDF document text
    • http://kinel-hunter.ru/upfiles/file/40569195840.pdfIn PDF document text
    • http://homestationrealty.com/userfiles/files/vuripi.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/hsbd7muh40mb2gem2gnqkkupk9/sobotalegilenajesedisojev.pdfIn PDF document text
    • https://www.comperat-89.fr/ckfinder/userfiles/files/pokusa.pdfIn PDF document text
    • http://lovec.bg/root/ckfinder/userfiles/files/15927726620.pdfIn PDF document text
    • http://fluitec.fr/ressource/site-image/files/dudofitemukululum.pdfIn PDF document text
    • https://rheinfurth.de/userfiles/file/raxowe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=sword+art+online+progressive+light+novel+epubPDF 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_off0000ce6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE6A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e67c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE67C 17688 bytes
SHA-256: 47ac5d851fe31944f01dc32c73139a884672cc6ca8c3bf7351f96b00e2390b56
font_02_sfnt_off00011469.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11469 11140 bytes
SHA-256: 8a38246a83df7895bba79ad22b07c623df9ed618ec36fc2d964afb3c263ad29d