Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c037c85d0746728…

MALICIOUS

PDF

88.3 KB Created: 2021-06-26 01:03:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 03e2cbc7f1eab6ed851ce68ba3d20719 SHA-1: d9238691728010a5e47b29737003605c70fdfcac SHA-256: 5c037c85d07467285b78b3cb84634208846e2212d4c65dfd2a0a1c2dbf239403
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The heuristics indicate it functions as a link farm, directing users to compromised WordPress upload storage and other disposable hosting sites. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, a tool often used to create PDFs from web content, further supporting the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 7

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://shethof.ch/cgi-bin/dynamisch/file/46051295535.pdf
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/8k4ibrvigi0ld7t09lmpg1g994/62934521643.pdf
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/sb1opqstuq1q5dflvv2g6n347p/golabenijol.pdf
    • http://www.jobsincrete.gr/images/_user_na/file/61306798196.pdf
    • http://kondicionery-ivanteevka.ru/upload_picture/file/fiwudik.pdf
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3cd5c5d4cf---mijibenaki.pdf
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1609aecb636c0a---buluxoxub.pdf
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a698d103f4b---37445072119.pdf
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/f353f0c631ccdf972b051de131bdae86/zukimidobovodopase.pdf
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/b609948c5f93b8c5bfc02b806d4c9377/70972205490.pdf
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c294a5aa8e---56476243029.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160b3718a7e9a3---norumosagusumezulafatifu.pdf
    • https://himalayanthailand.com/image/upload/File/xewamivefunaxinisunulixig.pdf
    • https://marljivo.hr/UserFiles/files/81048476464.pdf
    • http://jerseybankruptcylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jofalozulofalupujujotu.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/993621f862a91989017b63e587fe9cba/83232478460.pdf
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/f3825bdb117c18d1cad71772768a5a4f/18960882611.pdf
    • http://sherwoodchambergolf.com/ckfinder/userfiles/files/pinuvubajupedekixeni.pdf
    • https://detmers-kontejner.hr/files/kusapevi.pdf
    • http://akcjonariusz.com/UserFiles/file/wokudelilo.pdf
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/4hb8v3hn4use3kp3ipf52hl3bi/jebubajapabixixadad.pdf
    • https://blindnow.com/userfiles/file/leker.pdf
    • http://csc-021.com/userfiles/file/20210619131422_5ghhaa.pdf
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c1631d8d073---jaxeberigorajul.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=mdf+and+hdf+wood
    • 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_off0000f942.bin
5b4fcaab902ba1a1399cd874ecb40654dc7d963348368c442fef19766b2b3090
pdf-font-stream PDF embedded font (sfnt) at offset 0xF942 17204 bytes
font_01_sfnt_off00012659.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12659 16792 bytes
font_02_sfnt_off00013e6f.bin
27e80e334a8867905456e58743f826b8b72982ccda01340e8fdce2f5a20c8efd
pdf-font-stream PDF embedded font (sfnt) at offset 0x13E6F 9896 bytes