Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b74476d3727bc81…

MALICIOUS

PDF

76.9 KB Created: 2021-09-19 10:36:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 0b9d312259a3f737f99de31a910f450c SHA-1: aab3910fd1fc46df5c7eee8ce9b6729a7ff02040 SHA-256: 1b74476d3727bc812d28b0f5749301c72bb094cee4e8dec2deff5417de663592
94 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV with a 'Pdf.Phishing.Trojan' signature. Static analysis revealed it functions as a link farm, embedding a large number of URLs, many of which are hosted on disposable domains. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a deliberate attempt to manipulate search engine results or distribute malicious links. While no scripts were explicitly extracted, the nature of the PDF and the embedded URLs suggest it is designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.3127

Heuristics 4

  • 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
  • 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://selapro.com.au/application/third_party/ckfinder/userfiles/files/gupifobo.pdf In PDF document text
    • http://yetisirkaucuk.com/firma/files/28638739933.pdfIn PDF document text
    • http://motopujcovnateplice.cz/userfiles/file/64830978132.pdfIn PDF document text
    • http://thebrownbag.vn/upload/files/bumuni.pdfIn PDF document text
    • https://manhremhoangvan.com/wp-content/uploads/files/lisux.pdfIn PDF document text
    • https://bahia-group.com/ckfinder/userfiles/files/kubawagasanogomilixebo.pdfIn PDF document text
    • http://buyyoutubecomments.com/ci/userfiles/files/remanaro.pdfIn PDF document text
    • http://applexin.com/ttpsea/files/file/zapanepivuwizola.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b978da48a1---pomexuxa.pdfIn PDF document text
    • http://cadelupo.it/userfiles/files/saliporefoju.pdfIn PDF document text
    • http://restravel.ru/ckfinder/userfiles/files/jewumol.pdfIn PDF document text
    • http://czpohledavky.cz/userfiles/files/16861835341.pdfIn PDF document text
    • http://kashima.cc/userfiles/file/96533086304.pdfIn PDF document text
    • http://szilasfood.hu/pic_upload/files/8418221550.pdfIn PDF document text
    • http://chapaconoticias.com/assets/ckfinder/core/connector/php/uploads/files/mekepomejasutav.pdfIn PDF document text
    • https://lbjgold.in/ckfinder/userfiles/files/20732125177.pdfIn PDF document text
    • https://sinarlangit1.com/contents/files/40905284655.pdfIn PDF document text
    • https://leganordavigliana.it/uploads/file/37078577865.pdfIn PDF document text
    • http://hyundainhapkhau.net/upload/files/mokodakamimelobasefo.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161461ae9ba14c---45964486286.pdfIn PDF document text
    • http://kstarsmall.net/userfiles/file///pikomox.pdfIn PDF document text
    • http://avanti-kuhni.ru/upload/files/nubimafazuwukuvutoke.pdfIn PDF document text
    • https://limberhurstgallery.com/imageuploads/file/80812058370.pdfIn PDF document text
    • http://dgjinhak.kr/DATA/upload/files/202109140320116342.pdfIn PDF document text
    • http://vimbark.sk/editor_uploads/files/82097099750.pdfIn PDF document text
    • https://imaggu.com/ci/userfiles/files/bijinodexox.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=douchebag+simulator+unblockedPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dc09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC09 18112 bytes
SHA-256: bee4c0ad74be4938f80c84705eecea6e400b45286c37e1866dcefd5065ea77fc
font_01_sfnt_off00010b48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B48 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1