Malicious PDF — malware analysis report

Static analysis result for SHA-256 4400a9525a73b243…

MALICIOUS

PDF

81.9 KB Created: 2021-09-17 08:46:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: ca269d87729d721495d96a350f66cb9f SHA-1: 274ced9b12374ad2e80d3c79ca395356850cde30 SHA-256: 4400a9525a73b243ad85f4acf5fee23a98080df108fc5018c8ab249272057ac6
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://laborke.ru/uplcv?utm_term=duke+nukem+3d+android PDF link annotation
    • http://getwealthythisyear.com/ckfinder/userfiles/files/48002810989.pdfIn PDF document text
    • https://fuoriscena.eu/file/89014087853.pdfIn PDF document text
    • https://thietbixaydungcantho.com/canthomobile2/public/images/sanpham/files/91131968389.pdfIn PDF document text
    • http://saothienemb.com/uploads/images/files/zonipetukolijejaz.pdfIn PDF document text
    • https://henseltech.cz/userfiles/file/96577337441.pdfIn PDF document text
    • http://svadbavmoskve.com/content/xuploadimages/file/61066424406.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/5hg2psfsj80pc6nqjlddg69taa/zemoluwodozolifirepejare.pdfIn PDF document text
    • http://sake2metustin.com/uploads/files/pifokadujazojefusoz.pdfIn PDF document text
    • https://www.auto-ecole-acm.com/ckfinder/userfiles/files/dukidaxerokovevezabaki.pdfIn PDF document text
    • http://falerisztika.hu/tmp/51496838123.pdfIn PDF document text
    • http://hoitruyengiaocodocvietnam.com/uploads/image/files/kemadokuraleposegujikisuw.pdfIn PDF document text
    • https://ddshower.com/ckfinder/userfiles/files/figiraresigakotiwoxetap.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137c6522dd93---6919310614.pdfIn PDF document text
    • https://lnpro.in/ckfinder/userfiles/files/megimopiz.pdfIn PDF document text
    • https://anjingliar2.com/contents/files/nipaxivixesa.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/60845934089.pdfIn PDF document text
    • https://cdmsig2.com/ckfinder/userfiles/files/12919314891.pdfIn PDF document text
    • http://matras-devison.ru/upload/file/43501450569.pdfIn PDF document text
    • http://arredamentoambienti.it/img/file/5053642124.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130b329a4965---78080633253.pdfIn PDF document text
    • http://trivio.it/userfiles/files/9195072528.pdfIn PDF document text
    • http://studiotecnicoarduini.eu/userfiles/files/22530179387.pdfIn PDF document text
    • http://5mal4.de/moneyvidya/web/images/userfiles/file/1363987481.pdfIn PDF document text
    • http://www.pantonerestauri.com/ckfinder/userfiles/files/34115313335.pdfIn PDF document text
    • http://asqcert.net/files/files/70767074572.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_off0000deda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEDA 17076 bytes
SHA-256: 71c2e263973dd0eedaf8d3208231aa2bf881db6cbfb7d8b8be0777cbcb059bdb
font_01_sfnt_off00010aba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10ABA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000122d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122D1 10464 bytes
SHA-256: 8f993b96eac737703b39fefa6101dba656310551072101b91178287baa3d5c76