Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3e92bd3803a612a…

MALICIOUS

PDF

75.9 KB Created: 2021-09-17 15:56:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 9220744914df762d8a2de68e0d9c078f SHA-1: e186a10c89f70d96e59d56c6ae85a8f25efdeff5 SHA-256: b3e92bd3803a612a378d446cc3136dacf58d1690ff7dad7eb48f9f115cdd1513
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous links, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://ketchas.ru/uplcv?utm_term=best+android+app+for+drawing+comics PDF link annotation
    • http://bellina.pl/userfiles/file/59659600787.pdfIn PDF document text
    • http://eau-msu.ru/ckfinder/userfiles/files/nefavegexovekekurotut.pdfIn PDF document text
    • http://manchetenewsms.com.br/ckfinder/userfiles/files/60487663027.pdfIn PDF document text
    • http://xn--oy2b19v1mb1yi.com/userfiles/file/60321250195.pdfIn PDF document text
    • http://king-tableware.com/uploads/files/202109170216234372.pdfIn PDF document text
    • https://cs-nippon-cp.com/mailmagazine/upload/files/jixidodenufokejoweloj.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/32184431535.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/d8b89476cf64127ede9c5db622ec0ec4/siretobenavijezilesisofub.pdfIn PDF document text
    • http://artgrafika.cz/userfiles/file/94737375390.pdfIn PDF document text
    • https://koratspring.com/upload/file/parawuvu.pdfIn PDF document text
    • http://rspon.pl/images/wyswig_images/file/22563262681.pdfIn PDF document text
    • https://sukienmiennam.com/userupload/files/lepajefizazumikawuto.pdfIn PDF document text
    • https://hoya.hr/UserFiles/file/fesefovonavupozulurupa.pdfIn PDF document text
    • https://tunguoilon.tunhua.vn/ipp/images/uploads/files/felediwobedobuwadoju.pdfIn PDF document text
    • https://strategieb2b.ca/userfiles/file/nikilimoguxesilinowexe.pdfIn PDF document text
    • http://prepearl.com/uploadsfile/569754617.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/16136c7282ca8a---25632898533.pdfIn PDF document text
    • https://zlataraburmevuckovic.com/files/71183721949.pdfIn PDF document text
    • http://2446665a.ru/ckfinder/userfiles/files/tonelujubetibubujiraf.pdfIn PDF document text
    • https://kratky.eu/files/file/39329349789.pdfIn PDF document text
    • http://24hnbc.com/assets/ckfinder/core/connector/php/uploads/files/46300092725.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/1613e7f535171a---44382589071.pdfIn PDF document text
    • https://hotelangela.hu/userfiles/file/saletubabejeja.pdfIn PDF document text
    • https://www.nhabe.com.vn/ckfinder/userfiles/files/27431550456.pdfIn PDF document text
    • http://hoya889.com/upfile/files/20210904123508.pdfIn PDF document text
    • http://xn--989ap7r0xbd5x.com/upload/fckeditor/file/3846466594.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_off0000c58f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC58F 11056 bytes
SHA-256: c12e09492ad63118e0aae8fc7c0df92075ad151a16f524fc0fc69696827a0243
font_01_sfnt_off0000df31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF31 16728 bytes
SHA-256: 392399c09c5fe54d3ebc580d40820ee99a565fe964490f0aead9c76abe7056a8
font_02_sfnt_off00010a3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A3B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1