Malicious PDF — malware analysis report

Static analysis result for SHA-256 203796f3fbb69ac8…

MALICIOUS

PDF

89.5 KB Created: 2021-08-03 07:16:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 4c54b7b4af1d7bf8b82b1b7ec1adabe0 SHA-1: a7235b97775adfb45524f4b9443aec9390d22e91 SHA-256: 203796f3fbb69ac8ff4323dbcfdab43e0619b2d2d427285e96122c4d43bb19aa
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to websites hosted on compromised WordPress installations, suggesting a link farm or SEO poisoning tactic. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable, but the heuristic findings are sufficient to classify this as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/a0710ab909c45a50167335df5e1ab3a5/27163803720.pdf In PDF document text
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/49bdf513a5bb17e555c25771ce712b72/zutixuditedorum.pdfIn PDF document text
    • http://kagoshimakojintaxi.com/userfiles/file/85423815552.pdfIn PDF document text
    • http://studiotecnicobonoli.com/userfiles/files/91973285053.pdfIn PDF document text
    • http://kipia-nn.ru/userfiles/file/38996932451.pdfIn PDF document text
    • http://3bbb.fr/ckeditor/upload/files/34936154709.pdfIn PDF document text
    • http://haustechnik-hagenauer.at/41509317546.pdfIn PDF document text
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/728f3a6930a8b1fa338ba43b59a15b97/gabolafuvo.pdfIn PDF document text
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/c083a024e4e6f84ce2857e50972e146e/nofanurewu.pdfIn PDF document text
    • https://babamore.com/upload/ckfinder_temp/files/20210623222705.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/66bf4f104a3df63d596103c3fd4bb1a4/82550972702.pdfIn PDF document text
    • https://brs.jo/userfiles/files/83501827595.pdfIn PDF document text
    • http://stylowa-pss.pl/userfiles/file/ronojukalopinevulojavado.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/6bc68bc02f8eeab4680ed6895daa42ab/revolimozavevodi.pdfIn PDF document text
    • https://goez3.com/10005001208290177/ckfinder/userfiles/files/fikibigewabojimanifezozen.pdfIn PDF document text
    • https://www.xtremefitness.com.au/application/third_party/ckfinder/userfiles/files/nokore.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc01e32d60---43992477332.pdfIn PDF document text
    • https://ktmcollege.org/public_html/userfiles/file/tekafumowosifatumi.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/jqs7t4koj9frlraov333k3sb14/sepiponolezajetuzidup.pdfIn PDF document text
    • http://centrumbiznesurawicz.pl/userfiles/file/41239792004.pdfIn PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/k92p74i4e46ubd9bfnkcb5ksjr/wulavulo.pdfIn PDF document text
    • https://doluhosting.com/calisma2/files/uploads/nalevasepozodege.pdfIn PDF document text
    • https://andymullinscommercial.com/home/andy/public_html/ckfinder/userfiles/files/58440582504.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088448556751---rixifudanipozifatega.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160813b847d69c---tigaliv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=relative+pronouns+lesson+ks2PDF 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_off0000f664.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF664 18684 bytes
SHA-256: 3771ff0bea05ab5cee3d1d151e9837a24f44ea0a19f7c0d7eb902d996505c310
font_01_sfnt_off000126df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126DF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013ef6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EF6 10668 bytes
SHA-256: 443fdf10c04ba5eb784b92d0648f95a9f147a4973e9bf1ccfc44194fb14d1840