Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b5c1dc32d4c0851…

MALICIOUS

PDF

79.8 KB Created: 2021-04-06 08:27:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: e25fdbd36bdd4ff93f377e98a51e65d3 SHA-1: 2a2223519cc8a7a90028cf032d89b4acfdfb4630 SHA-256: 3b5c1dc32d4c0851600890ac6ef3f896bcc831cbe69ef9d5ff76428575e7c6f6
186 Risk Score

Malware Insights

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

The PDF contains a significant number of external links, many hosted on disposable domains, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. While no scripts were explicitly extracted, the PDF structure and numerous external URIs point towards an attempt to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://botokaw.ru/strik?utm_term=chef%2527s+choice+knife+sharpener+210+manual PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4415964/normal_6033e0c2f3546.pdfIn PDF document text
    • http://bidetoluji.getenjoyment.net/sistema_endocrino_organos_que_lo_componen.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4377933/normal_5fd7c2f463fd4.pdfIn PDF document text
    • https://wusowekop.weebly.com/uploads/1/3/2/7/132741020/6da869737b2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4462345/normal_6026bfca11f70.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4368956/normal_5fc68b17c954d.pdfIn PDF document text
    • https://tarokomilidifuz.weebly.com/uploads/1/3/1/6/131636676/a569b3dcde3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374953/normal_60675f123082d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413705/normal_60418c4444ea3.pdfIn PDF document text
    • https://poxofosu.weebly.com/uploads/1/3/4/3/134308827/774402.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388598/normal_601508dc8b834.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369933/normal_60388ff090d7b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4492588/normal_5ff26d71b8cf5.pdfIn PDF document text
    • https://mefufexuwi.weebly.com/uploads/1/3/4/0/134019004/vafuvagak.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://bowenadulopusin.rf.gd/bifodululet.pdfIn PDF document text
    • https://s3.amazonaws.com/wizidimawag/89762544577.pdfIn PDF document text
    • https://s3.amazonaws.com/tamobalasu/maletoxafinelemot.pdfIn PDF document text
    • http://genolewedusu.myartsonline.com/root_cause_analysis_techniques.pdfIn PDF document text
    • https://s3.amazonaws.com/tobovunoberiki/einfache_gleichungen_lsen_aufgaben.pdfIn PDF document text
    • http://zorijefugixor.atwebpages.com/ridikedopamonozaluf.pdfIn PDF document text
    • http://mimojududike.epizy.com/wafopuwelixuboperuko.pdfIn 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_off0000ed86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED86 5504 bytes
SHA-256: 8d17f5e73374421bee6e62db3906f63ba297406d02a504b8687604be88b32cfb
font_01_sfnt_off00010013.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10013 10568 bytes
SHA-256: b6a39ee883964f6f62fcf6a266e9133ceb1c1660232b1144f104c8e90bc5521b
font_02_sfnt_off000123c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123C2 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e