Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3ec963e288d0351…

MALICIOUS

PDF

70.3 KB Created: 2021-05-28 21:44:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 4721c8f1b6bfe22ace88ca1a1d99dff7 SHA-1: 50d3fe7336dd031c491ea80b93ca117e0c56e435 SHA-256: e3ec963e288d03510fb54cb9cd150e52ac28897276e0bc2bb1e287a1f461b8a5
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was identified as malicious by ClamAV and an ML classifier, and exhibits characteristics of a PDF link farm. It contains numerous external URIs pointing to various PDF files hosted on multiple domains, some of which appear to be disposable. This suggests an attempt to manipulate search engine results or distribute further malicious content through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://leonvi.ru/123?utm_term=blueant+q3i+manual PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4491934/normal_6012e3e344f00.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4488100/normal_5fd0673e82112.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485310/normal_6058c2c07b9ee.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4464732/normal_600c46321b38b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366676/normal_605179daa59a4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454172/normal_60418f45210c6.pdfIn PDF document text
    • https://bapixive.weebly.com/uploads/1/3/4/3/134393773/9b179fc10a0d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384836/normal_603c319c77136.pdfIn PDF document text
    • https://mosatidopo.weebly.com/uploads/1/3/4/7/134731439/66a8c35.pdfIn PDF document text
    • https://fisabovetusita.weebly.com/uploads/1/3/4/5/134597566/zefejalowine_lesij_dozixemibefuwit.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4383689/normal_5ff287f74e212.pdfIn PDF document text
    • https://lidubudizut.weebly.com/uploads/1/3/2/8/132815063/5979355.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366676/normal_5fdaef831455c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4378607/normal_6000d737c39f3.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4370088/normal_5fdf12c26fe7b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4379054/normal_5fcbf644bdf49.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4451044/normal_5ff7c2fd85da7.pdfIn PDF document text
    • https://kujuxase.weebly.com/uploads/1/3/4/5/134584075/74176.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/17c05d67-dbd5-4e13-ad95-9c0ed5eb6995/gomibur.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bb1f9722-864e-4fce-87b2-7e321d2a6ee7/feliz_navidad_de_jos_feliciano_acordes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9040c9d0-536a-4cca-8f16-45b18b1b5a35/childhoods_end_book_ending.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/98a998a1-de9e-4488-b0c9-c52e4f5c5dfe/nubogewavamug.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/46715240-b7a8-412f-8360-8bbed15692f8/can_someone_with_adhd_become_a_teacher.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_off0000d6f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6F2 4896 bytes
SHA-256: 0160f5314a32109e9d7242d321d2cbfc4b87b40d21ae53c0990c4da1f102dddf
font_01_sfnt_off0000e793.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE793 10860 bytes
SHA-256: b31fe4109ba875d1e769843f4b7cebc04f3a5d76022a3d0284bc708f9199a42d