Malicious PDF — malware analysis report

Static analysis result for SHA-256 55370a2cdbe7e2a6…

MALICIOUS

PDF

95.1 KB Created: 2021-09-06 04:23:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a09ca139c620f5c5c6604e944892759d SHA-1: 508246926c1895b497dd11a3e7286aec0f55f5dc SHA-256: 55370a2cdbe7e2a69be81506d2b848e0611b9344f05c0fd8179348e163c898a2
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL analysis point to a malicious link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9888

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 http://maynenkhiinverter.com/media/ftp/file/399828050.pdf
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608b1a5b055d9---22097599353.pdf
    • http://lagunaapartman.hu/images/user/file/4195143070.pdf
    • http://twozonechickenlasvegas.com/uploads/files/wejiteki.pdf
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/7899b67ca9d96936e3718ea73e610864/7326577942.pdf
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/cbca67e04eb242b15c2faa9828ae0a63/28052412104.pdf
    • http://yuc-fac.com/uploadfiles/20210821154853.pdf
    • https://itscebu.com/upload/file/20210903155914.pdf
    • https://kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/98837649115.pdf
    • http://strahovka66.ru/userfiles/file/93060260676.pdf
    • http://simsoncantho.com/userfiles/file/besokedubonepesego.pdf
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160dd9d1756820---6175312958.pdf
    • https://bikidi.com/UpFiles/WebEditorFiles/file/meradimufevapima.pdf
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160aaf711b00b7---40622137843.pdf
    • https://wavesmaroochydore.com/wp-content/plugins/super-forms/uploads/php/files/jf1u08ftu3l855gagvo2l83tve/gepulebuxokitomisipa.pdf
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/28c2999fb515817403b5dd819964613f/vudivitanazupoxax.pdf
    • http://flightshop.jp/images/blog//file/91259363735.pdf
    • https://www.zulilighting.com/wp-content/plugins/super-forms/uploads/php/files/e4c23c46f35bc1cfa267b90b5d2097ff/35487658680.pdf
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/1608d0c2ea35bb---38315531887.pdf
    • http://tnslib.net/userfiles/files/14687923607.pdf
    • http://dailythang.com/userfiles/files/88524810133.pdf
    • http://diysmart.net/userfiles/file/mepedetepagemojas.pdf
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16118fd93e2976---64213797493.pdf
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160beddec25209---32191984265.pdf
    • https://mlspoland.co/files/file/datofiwagupodewi.pdf
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085e3a076bd3---7399689646.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=soil+microbiology+pdf+books
    • 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_off00010c0d.bin
f3ead8b66804ef984e772cd441d42de498346143a227aa8f3de4c88e57abea56
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C0D 10888 bytes
font_01_sfnt_off000124b8.bin
2b6440af6397152e91b71945c8ba86595135a0f61530ae86a523e3661d09bcda
pdf-font-stream PDF embedded font (sfnt) at offset 0x124B8 18896 bytes
font_02_sfnt_off00015655.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15655 16792 bytes