Malicious PDF — malware analysis report

Static analysis result for SHA-256 628b33a819cc4664…

MALICIOUS

PDF

84.8 KB Created: 2021-09-11 14:13:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3497a70ce9d8050c21430ff8be6ca213 SHA-1: 0cd137ecdc69365f2618c3cbb98fe65686932fcc SHA-256: 628b33a819cc466469d76cd26806c66bfc5585ad11f5a6523c86b45c276722eb
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML and ClamAV as malicious, exhibiting characteristics of a phishing or malware distribution campaign. It functions as a link farm, containing numerous embedded URLs pointing to external PDF files hosted on various domains, some of which appear to be disposable. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using multiple distinct hosts with few links per host, suggesting an attempt to obscure the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://fcraregistration.com/UploadedData/file/88923854257.pdf In PDF document text
    • https://ebooksweb.net/files/file/keferubatatijikejo.pdfIn PDF document text
    • http://schokozentrale.de/idata/jedoberavifol.pdfIn PDF document text
    • http://sahrugs.com/userfiles/file/83033259550.pdfIn PDF document text
    • http://panhongbo.com/ckfinder/userfiles/site_eachfun_com/files/wijizokotide.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16134ba50a509b---xedonu.pdfIn PDF document text
    • http://teplo76.ru/uploads/file/dexupogulasemiwigiro.pdfIn PDF document text
    • http://tecsun-moscow.ru/docs/file/42291319471.pdfIn PDF document text
    • http://risorsaterra.it/userfiles/files/51339684631.pdfIn PDF document text
    • https://vhssirimpanam.org/ckfinder/userfiles/files/42580150207.pdfIn PDF document text
    • http://xn--xhq021fvrwdth.com/d/files/tixuwanujojumufezelidoge.pdfIn PDF document text
    • https://alves.bg/ckfinder/userfiles/files/xaduxudaferaferezimew.pdfIn PDF document text
    • https://connatlas.com/home/conn/public_html/ckfinder/userfiles/files/vaxuseli.pdfIn PDF document text
    • http://website-design-company.in/dev3/damodar/ckfinder/core/connector/php/userfiles/files/16094128300.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/161346d06b159c---17999831089.pdfIn PDF document text
    • https://lemarko.com/userfiles/file/63681655738.pdfIn PDF document text
    • http://kaushalacademy.org/ckfinder/userfiles/files/48613987651.pdfIn PDF document text
    • https://alstar.uz/images/shared/file/92864098889.pdfIn PDF document text
    • https://fwstc.in/userfiles/file/80407721339.pdfIn PDF document text
    • http://taxilitomerice.cz/ckfinder/userfiles/files/jurabizofariwejusejipaz.pdfIn PDF document text
    • https://singhaniabrothersltd.com/ckeditor/ckfinder/userfiles/files/begedokaxafilegonajex.pdfIn PDF document text
    • http://crmrealty360degree.in/userfiles/file/3762353984.pdfIn PDF document text
    • http://ottotech.center/userfiles/file/53350797005.pdfIn PDF document text
    • http://styrexon.cz/userfiles/file/14639444435.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=oxford+discover+grammar+3+answer+keyPDF 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_off0000e0c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f8e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8E0 11332 bytes
SHA-256: fbbec99132fe0672d7d585ee1a9581bc7aab6b578e10ff23abd8b6824e1a7f5e
font_02_sfnt_off0001137b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1137B 18768 bytes
SHA-256: b23949c99d16a2888f009bc9316a5db063e25c2a51f446492da97a0ede96c375