Malicious PDF — malware analysis report

Static analysis result for SHA-256 2982a88089c6f185…

MALICIOUS

PDF

72.4 KB Created: 2021-04-23 10:51:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: eaf2c253cde22f839383db5876c1b888 SHA-1: 3476e3573724af17e88afe87ac81dd99dad9f674 SHA-256: 2982a88089c6f18527439cbe9b8ccd0302d438af0830be0417576be04acdcf0f
126 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs, with one prominent URL pointing to zajinet.ru, suggesting a phishing or malware distribution attempt. The document body, though heavily obfuscated, appears to be a lure related to calculator brightness, which is a common tactic for disguising malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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 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://zajinet.ru/strik?utm_term=how+to+adjust+brightness+in+calculator
    • https://cdn-cms.f-static.net/uploads/4446634/normal_606b30850f3ea.pdf
    • http://viniveba.mywebcommunity.org/22187103642.pdf
    • http://napufokotipo.getenjoyment.net/carbon_fiber_properties.pdf
    • https://static.s123-cdn-static.com/uploads/4476268/normal_5fe0d6d233850.pdf
    • http://noxogejukebe.mypressonline.com/runoz.pdf
    • https://cdn-cms.f-static.net/uploads/4476596/normal_60466c2f3bfbe.pdf
    • http://gazedalepi.sportsontheweb.net/analects_of_confucius_with_explanation.pdf
    • https://static.s123-cdn-static.com/uploads/4495994/normal_5ff8bf1fb0946.pdf
    • http://vaxisezawoged.scienceontheweb.net/laxorijizixav.pdf
    • https://cdn-cms.f-static.net/uploads/4485578/normal_603b1ead43bac.pdf
    • https://cdn-cms.f-static.net/uploads/4458428/normal_601146c7bbf9b.pdf
    • https://static.s123-cdn-static.com/uploads/4465538/normal_6009a4280b92b.pdf
    • https://cdn-cms.f-static.net/uploads/4417305/normal_601446a249991.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/5312c90d-e705-4a65-931a-6e541765eecd/how_to_reset_zebra_zp_505.pdf
    • https://uploads.strikinglycdn.com/files/28a345fe-66f6-4afc-9127-4367d3a34fb3/nutemulaz.pdf
    • https://s3.amazonaws.com/kefiperizonofu/medical_equipment_specification.pdf
    • https://s3.amazonaws.com/kuboki/depirubufuronawewe.pdf
    • https://uploads.strikinglycdn.com/files/b375c2bc-e5bb-4700-a0b7-08bf35e3d365/90442825090.pdf
    • https://s3.amazonaws.com/bitajemisajoz/amdocs_online_test_questions_for_manual_testing.pdf
    • http://kewevagisugimuw.onlinewebshop.net/33034459958.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d404.bin
a28fcc4ba65d8171a55e8b87d646ac5d1dd213f66ab2b0026fd39e5ca5d32d1a
pdf-font-stream PDF embedded font (sfnt) at offset 0xD404 2900 bytes
font_01_sfnt_off0000de46.bin
b6f920fd25d79ce57d1d57030700c5092695e86387645d2f989ae6f8cc06dba9
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE46 5468 bytes
font_02_sfnt_off0000f0e9.bin
5fc504934b16e723918d54365565361093f257abf3cadc18e231bf71401a6904
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E9 10256 bytes