Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b9eb2b1a63004b3…

MALICIOUS

PDF

82.6 KB Created: 2021-09-19 10:36:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 164c66244c64b1f73c8bbeda2cdc1649 SHA-1: f2702b2840e4d3cf26a1bbdbbd373452f173f283 SHA-256: 7b9eb2b1a63004b332bafc3677f7c67dd7796fcd8ba8d10519296ba510e7a1e9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to domains that appear to be part of a link farm, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The file's structure and numerous external links indicate an attempt to redirect the user to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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 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://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_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
font_02_sfnt_off0001235f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1235F 11152 bytes
SHA-256: 0a6ff1d5ce639075535ed035fdd74e72f86c09e0b12640116a70672efc36111f