Malicious PDF — malware analysis report

Static analysis result for SHA-256 d939cc45053956e7…

MALICIOUS

PDF

87.3 KB Created: 2021-09-04 20:29:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 309b37acd9fbbbae086af50bdb15f4d5 SHA-1: 06fa5f13fa034a65db2f68f337a63f371e5f2d6c SHA-256: d939cc45053956e7176f6c80337b115dbdd6f8a202e19d6e4be1bf1d7ba44057
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document is designed as a link farm, likely to manipulate search engine results or redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, with the embedded JavaScript potentially serving as a downloader or redirector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://malopolskiszlakwinny.pl/upload/File/sigemipazafavopufunosu.pdf
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5ba89b45b5ea0f642be20b345519e7be/32761892560.pdf
    • https://speakingparrot.com/upload/ckfinder/files/66755271880.pdf
    • https://sofahatinh.com/upload/files/12734919451.pdf
    • https://stijsr.com/userfiles/file/45586213425.pdf
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/e2dc5bacb647b668434b954503df1650/nivitesa.pdf
    • https://echipamente-scule.ro/userfiles/file/18684327079.pdf
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/161029c257618d---99466444336.pdf
    • http://dagmar-e.de/userfiles/file/27938629545.pdf
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/1473b1a5404acfd8d18475339d290ea1/70762235328.pdf
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b9d78c9a3a4---vejixowupeturulejaxasebip.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160bab979ded1f---belosoresufanababetide.pdf
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9a650b3c49---rupavixaxovigiwoxunogija.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b9648ecc4c3---duvuke.pdf
    • http://aweibel.com/Photo/file/6384572810.pdf
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a985634e531---46222002535.pdf
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/16115e43c720da---65575671778.pdf
    • http://mediasingrid.com/js/new/fckeditor/userfiles/file/tunawo.pdf
    • https://www.eoluk.com/wp-content/plugins/super-forms/uploads/php/files/j8lsqei92ku2aft8fq5g6r29t6/70859761824.pdf
    • http://elfuklid.cz/foto/Image/file/fonavidajewukuramosez.pdf
    • https://ethnicminorities.heephong.org/ethnicminorities/cmsadmin/ckfinder/files/faxegobisi.pdf
    • http://thewellmanteam.com/userfiles/files/31936694056.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c5ead7f9c8---11648535224.pdf
    • http://beepost.vn/upload/userfiles/files/15885250099.pdf
    • http://connect-event.fr/ckfinder/userfiles/files/bibibazifuwubepor.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=stadium+ulkus+dekubitus+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_off0000ece9.bin
32c7a44b60a2c8b631d02082b6cbba71a4b8ee2b425ddfe07b128711acbd3d83
pdf-font-stream PDF embedded font (sfnt) at offset 0xECE9 19160 bytes
font_01_sfnt_off00011d97.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D97 16792 bytes
font_02_sfnt_off000135ae.bin
e5af9c2212223a404a9b5ba53a82ea49154a9bc322f9e0766fa438429ae00652
pdf-font-stream PDF embedded font (sfnt) at offset 0x135AE 10744 bytes