Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6d77366411053d9…

MALICIOUS

PDF

87.7 KB Created: 2021-09-19 01:00:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: cf232b7ea52e1f7c4f085951d5634b90 SHA-1: 518caa2a6ad794840a41057594a486e1bfbd2a6b SHA-256: c6d77366411053d950dd5ba1f0571f6e927cc230db87ccb33c65030ad0dedb5a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF sample was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs, many pointing to potentially disposable domains, suggests a link farm designed to obscure the ultimate destination, likely a phishing or malware distribution site. Although no scripts were directly extracted, the PDF structure and heuristic firings strongly suggest it's designed to exploit vulnerabilities or redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://rabudiagnostic.com/userfiles/files/kaluludogoviju.pdf In PDF document text
    • http://exito-opakowania.pl/userfiles/file/vaxubir.pdfIn PDF document text
    • http://www.tamtrebinhminh.com/public/files/nusel.pdfIn PDF document text
    • http://tulga.ru/editor/files/23400942701.pdfIn PDF document text
    • https://ww150006.linebot.net/upfile/files/20210901091554.pdfIn PDF document text
    • http://designerhouse.ru/upload/files/pugasigod.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/sazazasotoj.pdfIn PDF document text
    • http://novo-foto.ru/ckfinder/userfiles/files/radaximenewesomen.pdfIn PDF document text
    • https://esterkins.de/ckfinder/userfiles/files/zutosekerajananezesodojex.pdfIn PDF document text
    • https://liur-krd.ru/userfiles/file/podulokezuna.pdfIn PDF document text
    • http://tgroupsrl.com/userfiles/files/fakogipivikovamugixez.pdfIn PDF document text
    • http://delta-serwis.pl/pliki/30104227031.pdfIn PDF document text
    • http://trevelci.ru/ckfinder/userfiles/files/safekadipunam.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/92831151142.pdfIn PDF document text
    • http://uteambio.com/upload/files/rimigumodimoledakogulu.pdfIn PDF document text
    • http://i-akparat.kz/ckfinder/userfiles/files/93930451531.pdfIn PDF document text
    • http://predit.ru/admin/ckfinder/userfiles/files/ripugezufukugenezizifo.pdfIn PDF document text
    • http://studiotecnicodavico.eu/userfiles/files/82767412752.pdfIn PDF document text
    • http://technoprofile.ru/userfiles/file/98756023725.pdfIn PDF document text
    • http://ingore.cn/upload/files/lupaleziwote.pdfIn PDF document text
    • https://mebelihome.ru/upload_picture/lijebesupova.pdfIn PDF document text
    • http://sambometal.com/dataroom/file/kotijobelejiwezuj.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/rc7a0788bbdabsbb8h6f6isk9q/49109536160.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/16c082c6e6de5fd04a4551cc20f4b5d1/53316484578.pdfIn PDF document text
    • http://baaningdoi.com/file_media/file_image/file/24183518130.pdfIn PDF document text
    • http://duszek-lasu.pl/userfiles/file/37990246793.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=japan+lonely+planet+pdfPDF 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_off0000f0ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0CE 10236 bytes
SHA-256: 0e328c38b2f517fefe985350c400e5013833a71ec9b2409aa7b7a78849985052
font_01_sfnt_off000107f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012009.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12009 18908 bytes
SHA-256: 81f73421abc414aab85c8404e3e0e51f5b00603e69c329c27bb9d81d6fd2ef60