Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7d9938c0ccfa091…

MALICIOUS

PDF

76.3 KB Created: 2021-10-08 07:43:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7ffc337e903c399f7c79712126f8c6c4 SHA-1: bf7a1b72de58f6b9802839df5274cd5307e298ab SHA-256: c7d9938c0ccfa0913e7cb5975548d0ff4bdc3c3fa8208e19142117e0af55a0c4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://wastran.ru/uplcv?utm_term=tennessee+walker+dog
    • http://tjjjsh.com/uploads/files/denetozil.pdf
    • http://hatowo.com/app/webroot/uploads/files/45458216591.pdf
    • http://dxqzx.com/ckfinder/userfiles/files/20210907_200113.pdf
    • http://pvvc.cz/files/6715145800.pdf
    • https://regiefranchet.fr/userfiles/files/50599206857.pdf
    • https://rumusjitu.com/contents/files/ruzofinemosukaxus.pdf
    • http://iweldbot.com/ckfinder/pho/files/62665473974.pdf
    • http://photo-poligrafic.ru/ckfinder/userfiles/files/kakupinugag.pdf
    • http://xn--franzsischebulldoggen-lec.eu/userfiles/file/69744001384.pdf
    • http://ugrctrani.it/userfiles/files/79065558270.pdf
    • http://china-guolin.com/filespath/files/20210912005709.pdf
    • http://www.fan-consultants.com.tw/ezadmin/ckfinder/userfiles/files/50084617443.pdf
    • http://mayjack.com/upload/files/5481480198.pdf
    • https://topupdana.com/contents/files/ribotixox.pdf
    • http://hunicorn.hu/userfiles/file/24986935907.pdf
    • http://valkexclusief.reviews/app/webroot/files/userfiles/files/tupux.pdf
    • http://offerseir.com/basefile/offerseircom/files/derepupapiluxifobeg.pdf
    • https://wasael.com/userfiles/file/70906969308.pdf
    • http://www.ambatownship.com/ckfinder/userfiles/files/zofebutofejesitedotiki.pdf
    • http://dglytbt.com/upfolder/e/files/20210902110328.pdf
    • http://tnslib.tools/userfiles/files/89958047039.pdf
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/fe168e36558b122286ed618d98c7ed31/zemitidikabuma.pdf
    • http://www.kyousei-fukushi.or.jp/system/ckfinder/userfiles/files/fidudetub.pdf
    • http://ip-golubev.ru/ckfinder/userfiles/files/38404467628.pdf
    • http://atrsara.ir/resource/files/35089543542.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c841.bin
acc1b1b3d0eeaa415c296f1c069e537b92be3d54c1a98c41163fd218cd21f339
pdf-font-stream PDF embedded font (sfnt) at offset 0xC841 10376 bytes
font_01_sfnt_off0000dfb3.bin
61bfce168ba2d40c1d30ca56f9aceb0557e1e87e1402a5fafc1874effbe67173
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFB3 16928 bytes
font_02_sfnt_off00010b24.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B24 16792 bytes