Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e3ce380e0a8e101…

MALICIOUS

PDF

80.7 KB Created: 2021-05-28 00:32:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: a0c8758f2a9947cab184c87018ef8436 SHA-1: eb731659d8cd196582ea197c2d8fe1863bd68f38 SHA-256: 8e3ce380e0a8e101277d816546fc5cf9f65ca1eea31231c24f268df125419528
186 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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • 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://vilenefex.ru/strik?utm_term=morfofisiolog%25C3%25ADa+humana+tomo+2+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4366377/normal_606880c6417f8.pdfIn PDF document text
    • https://refapezi.weebly.com/uploads/1/3/4/9/134904673/616719.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470543/normal_606c9788b6c05.pdfIn PDF document text
    • https://keroxoxelesiz.weebly.com/uploads/1/3/1/4/131452869/7970719.pdfIn PDF document text
    • https://tufefuru.weebly.com/uploads/1/3/4/6/134621659/puwidadokuguwabux.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4382772/normal_60032d7309d3f.pdfIn PDF document text
    • https://lixabepona.weebly.com/uploads/1/3/4/5/134530066/bezije_jowobukutulut_wiwigekuje_sudufemid.pdfIn PDF document text
    • https://falopizesolirod.weebly.com/uploads/1/3/1/3/131379111/b3bfe96b685.pdfIn PDF document text
    • https://punopisa.weebly.com/uploads/1/3/7/5/137516802/2168130.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393486/normal_60626457c121c.pdfIn PDF document text
    • https://derixajulinam.weebly.com/uploads/1/3/4/3/134356287/51c15c3143.pdfIn PDF document text
    • https://zakupiza.weebly.com/uploads/1/3/5/9/135960967/b74e0238.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4493920/normal_606591866b685.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476123/normal_606e61ee6d2fa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/21d3bd87-7d5e-45ed-a9cf-83ab56ca3926/43504201666.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/44acb3dc-778f-4f37-bd88-21e9c34e60f6/jalebomebasip.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/98bc3448-4bf7-4615-97b3-9d54210877df/weginirenotaxe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/da7f4698-2ac7-4236-9697-c9681b0b895c/88135978625.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6558a4c9-2464-4ed2-9b25-2b28664f46f7/george_foreman_outdoor_electric_grill_walmart.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/933321e6-49b9-4e37-875b-6e564d5be0ae/whirlpool_dishwasher_cleaning_guide.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1257be98-d27f-414b-9c9b-581aa3ce7eb1/43338609760.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f6e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6E1 5648 bytes
SHA-256: 9f6c278d0cea285842b1c12e136919ce0525f75afa4675fbc9755f572a8174fb
font_01_sfnt_off000109f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109F9 13604 bytes
SHA-256: b5243a016031a35506c8436badd8bea361b0a8bcb8bb7ec00cc7ebe9a59bc753