Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd5c3da84aa25a96…

MALICIOUS

PDF

88.2 KB Created: 2021-06-30 17:21:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4fa70357300cf62ea8fe1b1a5bb9cb4b SHA-1: 63a12aeb34ffc704e26d578a46bbd01bc54889be SHA-256: cd5c3da84aa25a9637a15733a47b3e8a234c166bcf79c7e48d62835da5f24a43
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to potentially compromised websites, suggesting it's used for phishing or distributing further malware. The presence of external URIs and link farm heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://wastran.ru/uplcv?utm_term=all+in+one+english+class+12+pdf+download
    • http://zaragozalawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/28590048702.pdf
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a692ed0e25f---61183076206.pdf
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c61a1437419---sagewuzoroxite.pdf
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/b3a8e48dfd570fbec204214952765976/kofuxirivuj.pdf
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1609f1e961262b---nuwuruli.pdf
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a1e0ebacc7d---kodokimudafenegiwen.pdf
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/5b197cbf37ba23b8e321f461cf128dbf/tobidarog.pdf
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/39344012751.pdf
    • http://pusancard.com/userData/board/file/11225821251.pdf
    • http://klasykarozrywki.pl/public/images/fck/file/japimebul.pdf
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/4cb6759ea9883351df472ff25ddbfbe1/dugonowumojulusa.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607014c1e8751---59345427755.pdf
    • http://primaria-ciocirlia.ro/media/file/kunebavexepix.pdf
    • https://cuacuonbentre.com/upload/files/61551584126.pdf
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/54abe7f380e9f063c46701152602923c/848443786.pdf
    • http://alkanboya.com/files/file///22925658007.pdf
    • http://asbazainville.org/userfiles/file/kefanofogefexazaf.pdf
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16089268ab98b3---wosunulijuv.pdf
    • http://adamlegal.com/userfiles/file/vubeteropivinerakudowafi.pdf
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/7549e86448017de0ba942cba3f5241aa/bofikekosevolimudod.pdf
    • https://jaukiaplinka.lt/ckfinder/userfiles/files/68297246663.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb780aaa7c---45726997919.pdf
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/u8p740cd9q7c49e01uam90m98b/fafovek.pdf
    • http://aisef.org/uploads/userfiles/file/file/78724411133.pdf
    • http://eurolocal.info/sites/default/files/images/file/16609822990.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_off0000f463.bin
bf4da6fba391b61f66f82669af53b370ff86ee23ec9bf612f6fe826dab16eeb6
pdf-font-stream PDF embedded font (sfnt) at offset 0xF463 17400 bytes
font_01_sfnt_off00012216.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12216 16792 bytes
font_02_sfnt_off00013a2d.bin
17a7865752910957f688034dbfd4b0b6e07b16064767d46f0e9d574548125076
pdf-font-stream PDF embedded font (sfnt) at offset 0x13A2D 10940 bytes