Malicious PDF — malware analysis report

Static analysis result for SHA-256 41758977b1bccafe…

MALICIOUS

PDF

86.2 KB Created: 2021-08-16 21:38:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 9898e69ba4165fb84039a4fdb7fc71d4 SHA-1: 5e46e2f736be9ec8a43facb88684a481e22e1cc1 SHA-256: 41758977b1bccafe2c3492303a1e25165c0bafdf69683357406af85325633082
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm pointing to compromised websites. The PDF contains numerous URLs hosted on various domains, many of which are associated with compromised WordPress installations, suggesting a phishing or malware distribution scheme. No scripts were extracted, but the presence of multiple external links indicates an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9543cc97a9---44954372594.pdf In PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/fa40f7b34c6d18578e430e75154e9c22/13907409604.pdfIn PDF document text
    • https://gangnampools.com/contents//files/wurotesumesuwiboziburu.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c7b93283744---5090474144.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160ba5cf22564f---dififaxitaxidesedepunab.pdfIn PDF document text
    • http://photographybynami.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b739e5d7866---fobopesewudu.pdfIn PDF document text
    • https://www.elshandmadedesign.nl/ckfinder/userfiles/files/kokenemun.pdfIn PDF document text
    • http://capthepcongtrinh.com/uploads/news/files/jiwoluj.pdfIn PDF document text
    • http://davidhammerstein.org/userfiles/file/42819781284.pdfIn PDF document text
    • http://banlinhkienlaptop.com/userfiles/file/46346043449.pdfIn PDF document text
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160b4d26aac88f---77480603640.pdfIn PDF document text
    • http://cobe-ing.it/userfiles/files/melijixugedatewa.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160720b10a214f---lowiziniwasafupol.pdfIn PDF document text
    • http://chip-chup.hu/upload/file/57964709741.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098b724c83fa---76423622877.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/9nv02o4pahihlq93kh1c1pbnsj/zirusas.pdfIn PDF document text
    • https://resulgame.com/calisma2/files/uploads/76194687213.pdfIn PDF document text
    • http://law885995.com/upload/fckimages/file/takolaxavukogiratu.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607cdf0924d95---27870404174.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/d34ed6226a5ee887010e0f7ad7433f12/zugujasezowiloxanowam.pdfIn PDF document text
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/26qfeam7v5piroomq5c1vuh8t0/runowijilufaze.pdfIn PDF document text
    • https://nutricionintravenosa.com/wp-content/plugins/super-forms/uploads/php/files/97e2ea1a6c384d4d29f3579d3bfc8a2e/68253973445.pdfIn PDF document text
    • http://beiwendq.com/userfiles/file/neviwalubiriwamujiwunula.pdfIn PDF document text
    • https://miaousland.fr/ckfinder/userfiles/files/4464933018.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=how+to+calculate+mass+of+one+sulfur+atomPDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eda4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDA4 17040 bytes
SHA-256: 65506f4f8c852ac2598696e8879e723a8acadc86dd560281660d15544a4abf6b
font_01_sfnt_off000119e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119E3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000131fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131FA 10584 bytes
SHA-256: 61a4c8a62027d07800c81d1a306c25cff40029942431ce02111c281f9be24731