Malicious PDF — malware analysis report

Static analysis result for SHA-256 7ad81ef79da5c27b…

MALICIOUS

PDF

73.2 KB Created: 2021-10-01 06:57:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: a2b0008167204adc160069aece86d661 SHA-1: 74c6b05b08a18bd50bfee017f1da20a7a6a83063 SHA-256: 7ad81ef79da5c27b01d04de1c0ea72ead171db31d7be9ee2ea634ee2917ed162
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to suspicious PDF files on various domains, suggesting a link farm or distribution point for malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further indicates a pattern of using disposable hosting for these links. While no scripts were explicitly extracted, the nature of the embedded URLs and the detection names strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/1615451a289683---24595819731.pdf In PDF document text
    • http://ambulatorioveterinariomariani.it/userfiles/files/gikilomavagosagaxavo.pdfIn PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/94817841403.pdfIn PDF document text
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/82218014609.pdfIn PDF document text
    • http://viral-list-monster.com/ckfinder/userfiles/publics/files/vijasoxumum.pdfIn PDF document text
    • http://rocincorporated.com/domain.com/images/dynamic_pages/file/ledekesokowofu.pdfIn PDF document text
    • https://uzunlarpeynir.com/dursun/upload/files/72563161675.pdfIn PDF document text
    • http://veterinariacomportamentale.it/userfiles/files/faxapif.pdfIn PDF document text
    • https://www.canoe.ro/Extras/ckfinder/userfiles/files/9085842440.pdfIn PDF document text
    • https://nhuadailoan.vn/upload/userfiles/files/teporamijedadokirulutido.pdfIn PDF document text
    • https://www.kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/tilemexoxuzorakedopowile.pdfIn PDF document text
    • https://ccaquebec.com/userupload/files/72013020460.pdfIn PDF document text
    • https://hiddencliff.kr/FileData/ckfinder/files/20210918_A56B548FB2D4392E.pdfIn PDF document text
    • http://kxqcgs.net/filespath/files/20210919114933.pdfIn PDF document text
    • https://faresaldabbous.com/uploads/file/vekutexubaxej.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/qckur6k78hcujjs8ev3vdhgvfv/12470450334.pdfIn PDF document text
    • http://mitsubishilongbien.vn/images/ckeditor/files/65811335219.pdfIn PDF document text
    • http://comlark.ru/userfiles/files/68587317550.pdfIn PDF document text
    • http://yilip.net/userData/board/file/92466351543.pdfIn PDF document text
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/fatatupov.pdfIn PDF document text
    • http://kokocurry.gm/userfiles/file/44799662565.pdfIn PDF document text
    • http://afro-safari.com/upload/files/kopikubolenegigutowi.pdfIn PDF document text
    • http://connect-event.fr/ckfinder/userfiles/files/lowosudemukowip.pdfIn PDF document text
    • http://www.detskaoptika.cz/ckfinder/userfiles/files/11603733623.pdfIn PDF document text
    • https://fullhousetourism.com/UploadFiles/file/20210922045442150.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=can+you+sync+itunes+to+androidPDF 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_off0000b7f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7F0 10560 bytes
SHA-256: c0c4931310eb8d70166acdabd1f89ad8f7cef9f28037849ef76c5d0d5e94a9cd
font_01_sfnt_off0000d03e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD03E 17532 bytes
SHA-256: bafe2b28379d43b582c69130eb19b125ead282c9ce75205c419dbab22f937e02
font_02_sfnt_off0000fd62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD62 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1