Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2a4384a778700d3…

MALICIOUS

PDF

78.9 KB Created: 2021-09-16 21:35:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 758f8331d079709ef6579dc99e985a75 SHA-1: 8c68d7632a707582ad51e1e4c7b0ebfcba804490 SHA-256: b2a4384a778700d3e9fc16a06cac355bf0ac3295b37754cc6eb138c40033a3a4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains a large number of embedded URLs pointing to various domains, suggesting a link farm or phishing campaign. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically indicates that the PDF is designed to host numerous links on disposable domains, often used for SEO manipulation or to distribute malware. No scripts were extracted, but the structure and URL distribution strongly suggest a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://catamma.ru/uplcv?utm_term=cara+flash+hp+android PDF link annotation
    • http://carzip.biz/files/uploads/files/wuponurobezimoxif.pdfIn PDF document text
    • https://lingchuanfloor.com/app/webroot/userfiles/files/5432478847.pdfIn PDF document text
    • http://xn----1-6cdapb2bdyqawnpcindqfc.xn--p1ai/media/file/99565684227.pdfIn PDF document text
    • https://behagi.eus/files/galeria/files/71242415538.pdfIn PDF document text
    • http://borneneskontor-landsforening.dk/userfiles/file/85172520843.pdfIn PDF document text
    • http://labonscafe.com/userfiles/98107013520.pdfIn PDF document text
    • https://heuresromantiques.com/upload/files/20431013385.pdfIn PDF document text
    • https://classykitchen.pl/web/uploads/files/81585158552.pdfIn PDF document text
    • http://cck-brno.cz/ckfinder/userfiles/files/9302966328.pdfIn PDF document text
    • https://www.stock2morrow.com/ckfinder/userfiles/files/zapalasovesoxapibotizesun.pdfIn PDF document text
    • https://leresto-niort.fr/images/userfiles/files/kosomisisili.pdfIn PDF document text
    • http://svaz-podnikani.cz/files/file/91208916283.pdfIn PDF document text
    • https://thehouseproduction.net/file/8046723566.pdfIn PDF document text
    • https://ashasuchikala.com/ckfinder/userfiles/files/66129484620.pdfIn PDF document text
    • http://orsini-blasioli.it/userfiles/files/tikoloxoz.pdfIn PDF document text
    • http://vitacanes.com/uploads/files/58333219016.pdfIn PDF document text
    • http://pescepiana.eu/userfiles/files/jibepasunekuku.pdfIn PDF document text
    • https://sinarwaja.com/account/files/kaketowemakosapuloded.pdfIn PDF document text
    • https://bmw-zona.ru/uploads/file/vumudotopewareta.pdfIn PDF document text
    • http://ecofincas.net/ckfinder/userfiles/files/31935409708.pdfIn PDF document text
    • https://asztromiskolc.hu/ckfinder/userfiles/files/wupivoluxokosoruvobemam.pdfIn PDF document text
    • https://zzwgjx.com/d/files/mevitifivi.pdfIn PDF document text
    • https://klcconsulting.eu/klc/file/sutisiwegibeviv.pdfIn PDF document text
    • http://agriturismolescuderie.eu/userfiles/files/nomifuzem.pdfIn PDF document text
    • http://computer-rudolstadt.de/upload/file/34683254319.pdfIn PDF document text
    • 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_off0000d436.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD436 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC4D 10396 bytes
SHA-256: cac104b730d9a2eb44ed8a6d4fe0f0cda7e037d151373f66f28ce14739d062ed
font_02_sfnt_off000103a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103A7 16332 bytes
SHA-256: 73a94810cf1aaaa787ed2ec54d1c53408e6a47461e1ce70cdf8161a1b5e95c9f