Malicious PDF — malware analysis report

Static analysis result for SHA-256 73ac1a6de75fa098…

MALICIOUS

PDF

77.5 KB Created: 2021-06-09 06:54:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: e88b6373c9cf5d891cc2473c775cabcb SHA-1: f4d99a6db7fa0460a4110e38419ce6931c3a9d32 SHA-256: 73ac1a6de75fa0982adad80c43095cc57e2a13fa932668736f430fa6d3424a99
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://krisoc.ru/uplcv?utm_term=coin+master+free+spin+cheat PDF link annotation
    • https://powermailer.in/userfiles/file/91269437939.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/2912cdc32ac8cd7d03a46e8b447b1981/48303045789.pdfIn PDF document text
    • http://jogforbigt.com/clients/6/61/61f7a61d17da296148a50ccd59c4a139/File/novigomu.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076c4cb1c979---pagemidipub.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5dd20a5aa---93787429538.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d0d1d6fa05---40950423167.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/7188463dc9e0663cc0c20aaeb8e13228/turafuw.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607d37768eea0---remorebuv.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608c0b5f0ec22---gukanebagaduzezojawop.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c019439cfc3---78232038240.pdfIn PDF document text
    • https://www.beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/64f88937d89d03b2e63a114838635ad8/tikekabidoxavafusifi.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16089af59e6d1d---52101614424.pdfIn PDF document text
    • http://warraichmeats.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077e2df2f0a8---27549283147.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/59c102ecd500ff37042ada9eba75c0b9/begukivabupolumuwijusuja.pdfIn PDF document text
    • https://www.heracles-hotel.eu/wp-content/plugins/super-forms/uploads/php/files/v4ft1ejp79ti8dvpnjvhb51nb7/93201191725.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/tqgtnomu814i9702gdgogit6u0/kujorulovewipef.pdfIn PDF document text
    • http://gtlmarinefuel.com/userfiles/file/39470238433.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e64a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE64A 5036 bytes
SHA-256: 5841e8c2eea93ea3fbd74bafed6982e6625c40462eb910c5f66f7938c9f27633
font_01_sfnt_off0000f730.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF730 10504 bytes
SHA-256: 92127747b7f06fa4be38877054e13d32e41818a28f3f4c0e33b0ff90f9679df9
font_02_sfnt_off00011b18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B18 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2