Malicious PDF — malware analysis report

Static analysis result for SHA-256 88b436a2be51427a…

MALICIOUS

PDF

75.0 KB Created: 2021-06-07 01:52:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 0738fc20824d8fe9acdf5c8f73fab0e2 SHA-1: bfb532d6886e3f741a308773b7b11924e2d5333f SHA-256: 88b436a2be51427abf74d82b3ce149dcfe6eaa3702d55cb05ed385f9ee13bc5b
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-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://cructi.ru/uplcv?utm_term=laptop+specs+for+autocad+2020 PDF link annotation
    • https://medgarlci.com/wp-content/plugins/super-forms/uploads/php/files/b1346420d9d661842f57972220b20cb5/mafededoje.pdfIn PDF document text
    • https://wecafephuket.com/wp-content/plugins/super-forms/uploads/php/files/dbct50joav9p5j0iuevb7raro0/jopijiretiku.pdfIn PDF document text
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/fef50f624c1f800cd62590637d0bf17d/fefexukax.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160afb4c89b016---23857935813.pdfIn PDF document text
    • http://hifimarkt.eu/kunden/kronhardt/ckfinder/userfiles/files/sigukiveneba.pdfIn PDF document text
    • http://shethof.ch/cgi-bin/dynamisch/file/17233990239.pdfIn PDF document text
    • https://hoangnhataudio.vn/media/files/bekibijizotosi.pdfIn PDF document text
    • https://marbellamohali.com/wp-content/plugins/super-forms/uploads/php/files/cedbe90af6f6190591ede2fe8e2a1a30/73251556118.pdfIn PDF document text
    • https://damsindia.org/admin/uploads/file/fudeweze.pdfIn PDF document text
    • http://www.firengo.com/userfiles/files/51736330353.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160933b954a16c---jufegevu.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080fc6bd6650---63356705809.pdfIn PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/caf91d99f7028a9e4ce70fd45476165a/xojikafupujixodan.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/2cc739344712e57477710fb15c5701b7/4305805799.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160a0668488286---39591179588.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_off0000dd3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD3F 5060 bytes
SHA-256: 50f5e1c8b9f16b081163c757af26a12f42a95c14fe62fc87745e808a74c21b00
font_01_sfnt_off0000ee82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE82 10076 bytes
SHA-256: b4b6f020612d9ed7101bbdecded19cde0e3b8c6e1e7c80f118a9c35639f39616
font_02_sfnt_off000110fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110FB 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2