Malicious PDF — malware analysis report

Static analysis result for SHA-256 16fb5877adfbe020…

MALICIOUS

PDF

72.4 KB Created: 2021-05-06 21:09:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0097fbf8143efc0827cd05edead48336 SHA-1: 90f80bf5fd741ce1537983dd12e711d5139528ee SHA-256: 16fb5877adfbe0207fe8bb701c7c5d61442983dfe040ec329b82698e117500e1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The file functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and disposable domains, suggesting an attempt to redirect users to phishing pages or download further malware. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/7d4b29e6664f6345ed268c54a4bdbe79/21087215260.pdf
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/1608c3c2f1cd84---nogobovulubowumabefatun.pdf
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8e557cc74---soxabedawuk.pdf
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607175569121d---14746695826.pdf
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/dea1db5b40fb4c50c46e84e034b31b81/50921182288.pdf
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/e7b275641797885f7dcf105b3429e331/sujagedaji.pdf
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070e2d4871b8---62547633094.pdf
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/dc3d0c5d8e0ef9272e373e3761d607a2/welejutazugusel.pdf
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/646031b83348307e4ec83049ed48304a/14917073600.pdf
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160785ff6d0d97---60910829221.pdf
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16092b926e5fe4---kewuduti.pdf
    • https://alatheir.com/atheirwsfiles/file/42445342804.pdf
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1607770a47fa48---42129092216.pdf
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a5b1a7b86e---83713867853.pdf
    • http://www.lifestaralberta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608abc8909f82---fumezo.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=alaipayuthey+songs++in+masstamilan
    • 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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dddc.bin
6bd519d81175fcd08c82c7c26cf40f06208ca0f24d734c41c0e5ccfa6e0e4ee0
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDDC 5228 bytes
font_01_sfnt_off0000ef8e.bin
1e0f617eb701b42167b45d5ce881a1934898452ccadc2c640a8fdcfca309468d
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF8E 10784 bytes