Malicious PDF — malware analysis report

Static analysis result for SHA-256 73b412fdd2188677…

MALICIOUS

PDF

81.5 KB Created: 2021-07-08 10:30:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 3679c32e6bc2bcf246234b7bbba00a3b SHA-1: 3778452240bfa0e8da31590f75052a9e4c73f73b SHA-256: 73b412fdd2188677fd4f6176828a8cf3fafbcacaa1ef2f0e5be01ffe3109ee3e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites, suggesting a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the presence of external links on compromised infrastructure is a significant indicator of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9797

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://unicorn-furnitures.com/d/files/doxesikujo.pdf In PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607adc90790c6---nelagozivadalaripuzonim.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/p4ldqn9ehlmp11bi20b70a0d6l/kilariwekotixozanobewukil.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/b5mmn2cqdcufmcthrpo731q474/83008343725.pdfIn PDF document text
    • http://matsonconstruction.net/userfiles/file/zedetaruwugelozoz.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160747e26f0cd4---jugovovigipekaru.pdfIn PDF document text
    • http://servmed.net/userfiles/file/razizus.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d90522f113f---kajotiwukunimija.pdfIn PDF document text
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/ovs7b0bvktc1uj5ok9ne6gd7p0/51783583668.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160db18e41e5fd---60489306005.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb848c2255---belozexevosavisowube.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607d1a8e878fa---18909998053.pdfIn PDF document text
    • http://bright-inter.com/file_media/file_image/file/sademetuvidejuravofug.pdfIn PDF document text
    • http://vdtonline.vn/static/uploads/editor/files/46279389610.pdfIn PDF document text
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/a28814d5b6e764de78e5d4967d7185ff/32042108065.pdfIn PDF document text
    • https://iaetindia.com/ckfinder/userfiles/files/zuzevemugejupigotoga.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16091c29b783c1---45225191338.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/160a8c0f61c4f9---kanuzexurekezitazuz.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/fb92e7250b69d41a7407b3ecbe8c4751/88250034447.pdfIn PDF document text
    • http://ongxoanhdpe.vn/upload/files/77771016790.pdfIn PDF document text
    • https://havanic.com/cache/fck_files/file/86793978989.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/23ed6d8918cd5eab6469a3b028f99233/kevavutolobeminurezimixe.pdfIn PDF document text
    • http://tourister.kr/userfiles/file/34580660204.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089d010c4e28---76986886440.pdfIn PDF document text
    • http://dailycan.com/userfiles/files/xezipupeze.pdfIn PDF document text
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/etrbj63o951ngfbh6bdq2mrjp1/85774404988.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=lcm+of+4+and+12PDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c839.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC839 10208 bytes
SHA-256: 9bf9347bad06b1905a2e10d4f0e6207e9f2b4c4f673b2e9c845eb9ecc4dbe7e8
font_01_sfnt_off0000df2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF2F 16252 bytes
SHA-256: bfc7ce51a1a9b37382af61f0075eb0cdb972126da031002d338643432d80e6e4
font_02_sfnt_off0000f50f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF50F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00010d21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D21 16488 bytes
SHA-256: a7d3be0818757aa7ffa7867af502bd851c932800d4cf4a78a9599d4ecfb9d116