Malicious PDF — malware analysis report

Static analysis result for SHA-256 80a52391f241e1d2…

MALICIOUS

PDF

82.6 KB Created: 2021-09-01 02:24:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 5a01b475f35e0624cf7c22a7b7fe690b SHA-1: 9aa1606c77276792c82d96614bf2a304ab5c032c SHA-256: 80a52391f241e1d2c74cb739408a6b491b4e52cfdc7a0e5e694cd2d0f73a42a7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to lure users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://biogenetec.tw/image/files/20210723_050008.pdf In PDF document text
    • http://dzbnf.com/upload/file///rixutukinapazixizodebezoj.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/70587738963.pdfIn PDF document text
    • http://museeducuir.org/upload/files/tixurejesujudi.pdfIn PDF document text
    • http://szkolaprzybranowo.pl/ckfinder/userfiles/files/59482523869.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b6418e65d8e---55392730999.pdfIn PDF document text
    • http://metisentry.net/ckfinder/userfiles/files/87672644884.pdfIn PDF document text
    • https://shih-tzu.ro/files/file/wuzaderopasakigimetu.pdfIn PDF document text
    • https://www.gryf-wet.pl/ckfinder/userfiles/files/56260867288.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/4kptj4irm218vbvr97na60pb73/vimifiteziwigovi.pdfIn PDF document text
    • http://logistra.fr/ressource/site-image/files/57418568198.pdfIn PDF document text
    • http://www.prieteniitehnicii.ro/documente/file/kikunemub.pdfIn PDF document text
    • http://luchetti.it/userfiles/files/38219610994.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d36a562bae5---54234951316.pdfIn PDF document text
    • http://www.iuoelocal870.com/kaizen/ckfinder/userfiles/files/jewusamoromomer.pdfIn PDF document text
    • https://botroul.be/uploads/99802888542.pdfIn PDF document text
    • http://iccarrentals.com/files/file/dojuxesuzokot.pdfIn PDF document text
    • http://guojingmall.com/userfiles/file///pakajaxigezixovozupaguxog.pdfIn PDF document text
    • http://artikos.pl/userfiles/file/81970491869.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081a90f2f75b---ligezakerefutidaxu.pdfIn PDF document text
    • http://wallawallahighschool1968.org/clients/75819/File/14571853871.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160d53fd487a4e---72753305664.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=thermodynamics+and+heat+transfer+notes+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_off0000d9be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9BE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f1d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1D0 18612 bytes
SHA-256: 36db71bdfce38b10492e5818798b79bb8ea734d2f1afb0b4a1cb4d0434548e6f
font_02_sfnt_off000121a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121A3 10916 bytes
SHA-256: 2ce9754ec84d5f1cb6002eb3023ca99af0cefdd4f11b648b46439eefd60dccfd