Malicious PDF — malware analysis report

Static analysis result for SHA-256 c78f3dda005dcb81…

MALICIOUS

PDF

68.7 KB Created: 2021-04-04 12:24:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: b23412071d101c65029da1185c391efe SHA-1: e7f000acb45be38897c3fb93b44b894a8a298755 SHA-256: c78f3dda005dcb81e28cb73d36e23c6fe8a82eac045286cbb9efb5b484505ed3
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 0.9996

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://nipisod.ru/wix?keyword=2000+cavalcade+publishing+molar+mass+worksheet PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4377647/normal_60605138dab32.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475728/normal_60308598dfde9.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4409621/normal_5feb2563950e8.pdfIn PDF document text
    • http://gapijet.scienceontheweb.net/magoja.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4380527/normal_5feb2702802cc.pdfIn PDF document text
    • http://roxelejabojafe.scienceontheweb.net/55703196081.pdfIn PDF document text
    • http://kitukotobov.medianewsonline.com/kitaaba_afaan_oromoo_kutaa_11.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470703/normal_5fe8b438b5e35.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465010/normal_60138da2ae5ab.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413455/normal_60419c83e9a2c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410030/normal_603f466a03cb8.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://gifidabula.atwebpages.com/national_immunisation_program_schedule_2020.pdfIn PDF document text
    • https://s3.amazonaws.com/gavapozalilup/pifizifigurakelilolirera.pdfIn PDF document text
    • https://s3.amazonaws.com/xufaxoferugod/shankar_mahadevan_tamil_songs_isaimini.pdfIn PDF document text
    • https://c0b8f06b-4e98-4d3d-89ef-2f08caba629a.filesusr.com/ugd/0c8cc8_0acd4283dad543e8906fa7faa43a1745.pdf?index=trueIn PDF document text
    • https://c3e810f9-371e-40b9-9a0b-4695a496ec77.filesusr.com/ugd/2c7c49_15c5d2caf094462abc50a2647520981f.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/takateg/juxaxozalokasenanejemos.pdfIn PDF document text
    • https://923a8ca3-316b-4844-b38f-9bc955ad4852.filesusr.com/ugd/312e0e_ea862224a6c64869a9231d6df8cc9f49.pdf?index=trueIn PDF document text
    • https://70010cfe-69b1-4fe9-a336-bdfe2418dc1e.filesusr.com/ugd/f1d680_0c3a6ceeec3a49408264d1329fa3c1cc.pdf?index=trueIn PDF document text
    • https://6184de0c-c318-42a7-882e-c5ddc63b817d.filesusr.com/ugd/1c8c1e_71a59333d9a9468797a4b5dc0e8d367e.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tobaziw/where_is_the_unloader_valve_on_a_ryobi_pressure_washer.pdfIn PDF document text
    • https://245ae9ba-e923-43ed-bc11-30ed5d1acd78.filesusr.com/ugd/051519_3a24ef26015544dcb3944de918abaff0.pdf?index=trueIn 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_off0000cc72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC72 6020 bytes
SHA-256: 0f2a4742d7d33ce434c77e0fda30e68a37834501078312dce2575a703079afa7
font_01_sfnt_off0000e0cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0CD 10200 bytes
SHA-256: e61e58edb8f20f2885881b136749843dff1f98b49629f8e20fd7573a7494c079