Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4c530c9afdf305d…

MALICIOUS

PDF

85.5 KB Created: 2021-07-01 18:10:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e6c2b8494c227f9c56848ab6c6a575fe SHA-1: aa3c061ed3506ed743689230487d8b03f54a9a23 SHA-256: f4c530c9afdf305d4133cedec6ce7fc028c92a54844fb6b1a8635b60c848ddb4
156 Risk Score

Malware Insights

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

The file was detected as a phishing trojan by ClamAV and flagged by an ML classifier. It contains a link farm pointing to multiple PDF files hosted on compromised WordPress sites, suggesting an attempt to lure users to malicious content. The PDF structure itself does not contain readable text, but the heuristics indicate a malicious intent through its use of external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608f72d3d5e57---ravirubenezusutuze.pdf
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160829cd7b8ba4---30005036945.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/fd49v1kd5mu3t28r61nbudvbsf/95122322456.pdf
    • http://karunb.com/UpLoads/files/88166173842.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/d40d499dcbe433fedf7b4d2596bbad92/wuduxilu.pdf
    • http://renovator.cz/files/file/magefozovanipozaza.pdf
    • http://moristas.com/userfiles/files/jukaziloxaw.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/a4a152ce06bc3b5c071759f0c9807850/pozojo.pdf
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160a82c32214e3---zevoratepi.pdf
    • http://zonweringbelgie.nl/ckfinder/userfiles/files/90174621052.pdf
    • http://capitolmetrophysicaltherapy.com/userfiles/file/ribalasiwelapu.pdf
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/6v86lo3me1bq9vpp4kmr9b2v05/2201910922.pdf
    • https://www.haievent.com/wp-content/plugins/super-forms/uploads/php/files/igm5c321fmhip88lc7t3ogmcfl/95639122979.pdf
    • http://abogadosaguilar.com/ckfinder/userfiles/files/lapagajota.pdf
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c4eb9a46076---84162147753.pdf
    • https://ayurvedaemart.com/uploads/file/jisogaxag.pdf
    • http://akcjonariusz.com/UserFiles/file/lirasuru.pdf
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/17429729865.pdf
    • http://aimic.com/userfiles/file/13107387273.pdf
    • https://arket.io/wp-content/plugins/super-forms/uploads/php/files/son82kp4ln5fe0q206jglt0cuu/58354828550.pdf
    • http://www.assignproject.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607289b45dd3e---72977959541.pdf
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/9tlraerub30ivqrkp1m5qcu4vn/58034808880.pdf
    • http://aci-immobilier-douai.fr/userfiles/files/91420583676.pdf
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607188993af0f---78294060951.pdf
    • http://spearsyounglegacy.com/clients/b/b2/b2c23f164518415ec8f3c1c8d0af542d/File/91770075980.pdf
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cef97e1a98b---jiwubifexupamigirane.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=the+spinous+process
    • 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_off0000ea01.bin
1669c423d59076c8c351f9a2b205c84d0253f526e9c17dcf57548d5631d291fb
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA01 19052 bytes
font_01_sfnt_off000119c7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x119C7 16792 bytes
font_02_sfnt_off000131de.bin
5d0a3b4dad434dba8422ecab65575de75df8bb2cd83f8841a1f54b45b562ffa2
pdf-font-stream PDF embedded font (sfnt) at offset 0x131DE 10228 bytes