Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a3ffada51d3d5a8…

MALICIOUS

PDF

68.4 KB Created: 2021-09-08 09:44:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f9c73df091c28211e1f9e8063424559e SHA-1: c7b26f2e4ba5cd52500ee4ff2cf1d443a5c4bf8e SHA-256: 7a3ffada51d3d5a84c0dde09580fad0d3e001af89bff5d27729dbc3aa670045c
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as a link farm, with several URLs pointing to compromised WordPress sites and disposable hosting. The ML classifier and ClamAV also identified it as malicious, likely a phishing or malware distribution lure. The document body is heavily obfuscated and unreadable, but the presence of numerous external links suggests an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://kudamatsu.org/userfiles/file/xutosofumiwina.pdf In PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/5751e036af0fbb6af7cb05d32ed941a6/98443162682.pdfIn PDF document text
    • https://sankaibearing.com/userfiles/files/84192311622.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/mm8a8cu9kc1dgrqg3s0efolsi4/23183018321.pdfIn PDF document text
    • http://budka39.ru/files/84212977025.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/wizuxe.pdfIn PDF document text
    • https://immsac.pe/sgi_userfiles/userfiles/files/sejevurulub.pdfIn PDF document text
    • http://ippon.lv/uploads/File/34636553332.pdfIn PDF document text
    • https://mojer.bg/files/zejadogipesezol.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/429b3f40716b20667f50a0f925023a9a/taxetuwufed.pdfIn PDF document text
    • https://tirthmobile.com/wp-content/plugins/super-forms/uploads/php/files/ho561ck8pirsk21ts5habdslq2/zewukaxidomubasil.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/6112d9b99ac207959dcd76d4831a4622/35733530058.pdfIn PDF document text
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/1606feb756657e---87582092232.pdfIn PDF document text
    • http://kondicionery-ivanteevka.ru/upload_picture/file/dapomozigazetesegefuna.pdfIn PDF document text
    • http://volker-issmer.de/userfiles/file/sotavefidugeresitipedolu.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/udp6b3maudi7rrhk4ehbsdmak3/789133558.pdfIn PDF document text
    • http://soepcentrale-dekeyser.be/userfiles/file/raziwalo.pdfIn PDF document text
    • http://cnzhongkui.com/fckeditor/editor/filemanager/connectors/php/uploads/file/070111284648.pdfIn PDF document text
    • http://precisao.org/files/files/miriwep.pdfIn PDF document text
    • http://vipnjl.com/userfiles/files/88440787730.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/161100d406eb6b---40440228188.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=3rd+grade+geometry+printable+worksheetsPDF 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_off0000ae4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE4B 11344 bytes
SHA-256: 79d2093f7eed9d59cb86b3b17ec1a42147fd9f2ef2d1bfa753aeb0d10ba14dc0
font_01_sfnt_off0000c869.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC869 14588 bytes
SHA-256: a8f981ec77bdbfbb58623c0800762a282d1262d6bb876bce296df71dc5161027
font_02_sfnt_off0000ec3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC3C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1